Modeling MSA and CSAs

[Erik]

Dodge will be added to the Omaha MSA and Saline will be added to the Lincoln MSA. Omaha - Lincoln should exist as a CSA according to the 2013 OMB definitions.

To Omaha: Total Primary Jobs 398,764 100.0% 376,514 100.0%
Omaha-Council Bluffs, NE-IA 345,536 86.7% 333,969 88.7%
Lincoln, NE 11,598 2.9% 11,691 3.1%
Fremont, NE 5,249 1.3% 4,673 1.2%


To Fremont:Total Primary Jobs 14,243 100.0% 14,536 100.0%
Fremont, NE 8,332 58.5% 10,095 69.4%
Omaha-Council Bluffs, NE-IA 3,165 22.2% 2,212 15.2%
Lincoln, NE 388 2.7% 352 2.4%


To Lincoln:Total Primary Jobs 147,954 100.0% 143,810 100.0%
Lincoln, NE 110,850 74.9% 119,989 83.4%
Omaha-Council Bluffs, NE-IA 14,900 10.1% 10,410 7.2%
Fremont, NE 1,027 0.7% 670 0.5%


Percent of Lincoln commuting to Omaha + percent of Lincoln's workforce from Omaha MSA = total
2000: 7.5% + 7.2% = 14.7%
2010: 7.269% + 10.1% = 17.369%

Combined Statistical Area—A geographic entity consisting of two or more adjacent Core Based Statistical Areas with employment interchange measures of at least 15.


Employment interchange measure—A measure of ties between two adjacent entities. The employment interchange measure is the sum of the percentage of workers living in the smaller entity who work in the larger entity and the percentage of employment in the smaller entity that is accounted for by workers who reside in the larger entity.

[Linkin5]

I'm not good at this stuff, so this means Omaha-Lincoln will officially be a CSA?

[Stargazer]

Although I'm not all that up on it... for some reason I was thinking it was 15% (or whatever the magic number is) in ONE direction... not combined.

[Erik]

Although I'm not all that up on it... for some reason I was thinking it was 15% (or whatever the magic number is) in ONE direction... not combined.

I was under that impression too until I read the new defintions by the Office of management and budgeting (OMB). They said it is the 'sum' of the percentage points.

http://www.whitehouse.gov/sites/default ... mplete.pdf

Employment interchange measure—A measure of ties between two adjacent entities. The employment interchange measure is the sum of the percentage of workers living in the smaller entity who work in the larger entity and the percentage of employment in the smaller entity that is accounted for by workers who reside in the larger entity.

And here is the new definition of the Combined Statistical Area:

Combined Statistical Area—A geographic entity consisting of two or more adjacent Core Based Statistical Areas with employment interchange measures of at least 15.

Previous definitions said 15% - 25% of the 'Employment interchange measure' required state legislature approval while the new definitions state 15% is now the threshold with or without the approval. Omaha - Lincoln had a 14.7% interchange in 2000 which has since increased to over 17% (almost 19% if you include the upcoming addition of Fremont to the Omaha MSA).

[BRoss]

Don't you guys know that 95% of statistics are made up? :;):

[iamjacobm]

Looks like it will be the ~38th largest CSA in the country when all said and done.

[almighty_tuna]

Good grief, about damn time. let's get an NFL team already. Criminy.

[Big E]

Good grief, about darn time. let's get an NFL team already. Criminy.

Let's see how this LFL thing takes hold. Baby steps, good sir.

[S33]

I can save you the suspense on the lfl. Omaha racers, nighthawks, knights, etc. As big Tom Callahan always said, its either NCAA or pro, there ain't no third direction.

[Big E]

Oh, sorry. I thought I was serious about that.

[Big E]

IN seriousness, though... does this put the Omaha- Lincoln - Fremont - Yutan - Wahoo megalopolis in that arbitrary meaningless magic Top 50 chart for demographics somewhere?

The one that gets us real retail options and direct flights to more than four cities?

[derog]

IN seriousness, though... does this put the Omaha- Lincoln - Fremont - Yutan - Wahoo megalopolis in that arbitrary meaningless magic Top 50 chart for demographics somewhere?

The one that gets us real retail options and direct flights to more than four cities?

Probably not.

[Erik]

I'll find out if that does put us in the top 50. I know it has to be close as the combined metro would put it at the 47th largest size with the 39th largest annual numerical growth.

[Stargazer]

Although I would guess we wouldn't be the only metropolitan area benefiting from this... if there indeed has been a change. We may just find our 'numbers' increase, while our relative rank doesn't change considerably.

[Erik]

The attached URL is the rankings of CSAs (also MSAs if they are not part of a CSA): http://www.apedesignware.com/data/MSA-CSARankings.xlsx

Omaha ranks #58 in size as a single MSA
Omaha - Lincoln ranks #51 in size as a CSA (against CSAs and MSAs)

Oklahoma City - Shawnee Combined Statistical Area OK 1,029,802 1,161,058 1,322,429 1,348,333
Hartford - West Hartford - Willimantic Combined Statistical Area CT 1,226,203 1,257,744 1,330,809 1,331,406
Grand Rapids - Muskegon - Holland Combined Statistical Area MI 1,083,178 1,254,846 1,321,557 1,328,440
Memphis Metropolitan Statistical Area TN-MS-AR 1,067,263 1,205,254 1,316,100 1,325,605
Greenville - Spartanburg - Anderson Combined Statistical Area SC 976,462 1,128,171 1,266,995 1,281,394
Richmond Metropolitan Statistical Area VA 949,244 1,097,113 1,258,251 1,269,380
New Orleans - Metairie - Bogalusa Combined Statistical Area LA 1,307,568 1,360,490 1,214,932 1,238,228
(Omaha-Lincoln-Council Bluffs CSA) 2013 Combined Statistical Area NE - IA 962,103 1,083,966 1,218,398 1,234,731
Buffalo - Niagara - Cattaraugus Combined Statistical Area NY 1,273,574 1,253,896 1,215,826 1,213,871
Birmingham - Hoover - Cullman Combined Statistical Area AL 1,024,281 1,128,766 1,208,453 1,212,800
Albany - Schenectady - Amsterdam (Capital District) Combined Statistical Area NY 1,097,335 1,117,979 1,168,485 1,168,120
Rochester - Batavia - Seneca Falls Combined Statistical Area NY 1,096,153 1,131,798 1,149,653 1,150,469
Fresno - Madera Combined Statistical Area CA 755,569 921,945 1,081,315 1,095,829
Dayton - Springfield - Greenville Combined Statistical Area OH 1,081,011 1,085,270 1,072,891 1,075,683
Knoxville - Sevierville - La Follette Combined Statistical Area TN 797,998 935,669 1,055,086 1,063,354
Tulsa - Bartlesville Combined Statistical Area OK 809,085 908,650 988,454 998,438

[iamjacobm]

From what I am reading Omaha and Lincoln are not being designated as a CSA.

[Bob from Omaha]

I thought it was related to commuters between the two areas, and there weren't enough. In the end does it really matter? When the Omaha metro goes over a million it's a milestone. If Streets' dreams come true some day and the two become one with a 20 lane highway between them then they will be a CSA.

[Erik]

Yeah i saw that. Above I had included the information provided by the OMB which stated the relaxed rules of what now constitutes a CSA and the update commute patterns by the state of Nebraska...

I don't know what to think... Maybe the state of Nebraska's commute pattern data is wrong or the OMB used a different set... Not sure and certainly not surprised by this.

[Erik]

I ran this by several engines to verify the numbers, and im going out on a limb again.

Two things happened that prevented this. First, my numbers were accurate in this thread and, get this, there was a mistake by our local leaders and the OMB. Then, in 2020, the pandemic happened which temporarily nuked the second try.

I was so embarrassed by my original fail that I just quit even looking lol. But I decided to take another stab at this.

Barring any weird circumstance with 2025 Omaha and Lincoln should easily become a CSA in the upcoming 2028 revision (looking at the 2021-2025 5 year average).

Code: Select all

+-----------+--------------------+---------------------+-----------------------+

|   Year    | 5-Year Average EIM | 1-Year Snapshot EIM |        Status         |
+-----------+--------------------+---------------------+-----------------------+

| 1980      | 9.2%               | 9.2%                | Separate              |
| 1990      | 11.8%              | 11.8%               | Separate              |
| 2000      | 14.7%              | 14.7%               | Separate              |
| 2010      | 15.2%              | 15.8%               | Qualifies for CSA     |
| 2020      | 14.9%              | 12.1%*              | Separate (Pandemic)   |
| 2023      | 15.1%              | 15.9%               | Qualifies for CSA     |
| 2024      | 15.6%              | 16.9%               | Qualifies for CSA     |
| 2025 (E)  | 16.3%              | 17.4%               | Qualifies for CSA     |
+-----------+--------------------+---------------------+-----------------------+

[Erik]

Where is was truly wrong was my dodge county MSA inclusion. Its very close, but we will have to wait at least another five years.

Code: Select all

+-----------+--------------------+---------------------+-----------------------+

|   Year    | 5-Year Average EIM | 1-Year Snapshot EIM |        Status         |
+-----------+--------------------+---------------------+-----------------------+

| 1990      | 12.4%              | 12.4%               | Separate              |
| 2000      | 15.1%              | 15.1%               | Formed CSA            |
| 2010      | 17.4%              | 18.2%               | CSA Only              |
| 2015      | 18.6%              | 19.5%               | CSA Only              |
| 2020      | 19.8%              | 14.2%*              | CSA Only (Pandemic)   |
| 2023      | 21.2%              | 23.4%               | CSA Only              |
| 2024      | 22.5%              | 24.1%               | CSA Only              |
| 2025 (E)  | 23.1%              | 24.8%               | Near MSA (25%)        |
+-----------+--------------------+---------------------+-----------------------+

[Erik]

Otoe is close also, but we will have to wait another five or so years.

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OFFICIAL COMMUTING FLOWS: OTOE COUNTY (ACS 5-YEAR)
------------------------------------------------------------------
METRO TARGET       2010 FLOW    2020 FLOW    CHG (PTS)
------------------------------------------------------------------
Omaha-CB MSA       18.2%        21.4%        +3.2
Lincoln MSA        12.8%        14.1%        +1.3
------------------------------------------------------------------
*Next official OMB review: Expected 2028.
*Threshold for inclusion: 25.0%.

[Louie]

That's cool to see, hopefully nothing gets in the way of that designation. That new CSA population as of the 2024 estimates would be 1,411,207. So closing in on 1.5 million by the 2028 revision.

[Omaha Cowboy]

I’ve thought, for several years now, the commute threshold numbers were in line to finally combine Omaha-Lincoln into a CSA. It’s only a matter of time. Let’s hope this happens in 2028..

Hopefully, once this happens, Nielsen and the TV Market designations will fall in line as well…

Ciao..LiO…Peace

[Garrett]

What’s the source for these numbers? Census data isn’t showing anything remotely like this

[Garrett]

And once again, here is census data that shows that, at most, around 2% of workers commute between Omaha and Lincoln in their respective markets. This is how the Census Bureau defines MSAs and CSAs.

https://www.census.gov/data/tables/2020 ... -2020.html

[Erik]

And once again, here is census data that shows that, at most, around 2% of workers commute between Omaha and Lincoln in their respective markets. This is how the Census Bureau defines MSAs and CSAs.

https://www.census.gov/data/tables/2020 ... -2020.html

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OMAHA-COUNCIL BLUFFS MSA (8 COUNTIES)
----------------------------------------------------------------------
COUNTY                 TOTAL EMPLOYED      COMMUTES TO LINCOLN MSA
----------------------------------------------------------------------
Douglas, NE            284,512             3,184
Sarpy, NE              96,120              4,105
Pottawattamie, IA      45,890              142
Cass, NE               13,245              985
Saunders, NE           11,150              1,765
Washington, NE         10,610              58
Mills, IA              7,150               22
Harrison, IA           6,890               12
----------------------------------------------------------------------
OMAHA MSA TOTALS       475,567             10,273 
(% of Omaha Workforce Commuting to Lincoln: 2.16%)


LINCOLN MSA (2 COUNTIES)
----------------------------------------------------------------------
COUNTY                 TOTAL EMPLOYED      COMMUTES TO OMAHA MSA
----------------------------------------------------------------------
Lancaster, NE          168,450             10,120
Seward, NE             8,620               315
----------------------------------------------------------------------
LINCOLN MSA TOTALS     177,070             10,435
(% of Lincoln Workforce Commuting to Omaha: 5.89%)

It was a hallucination. The total EIM is 8%. AI is rough to deal with. Im going to have to spend some time massaging these numbers to figure out why the AI messed up or if there is more to what its doing.

I need to look deeper for now.

[Erik]

Check this out. This is what the AI said:


I made them up. In the AI industry, it is called a "hallucination," and it is a complete failure on my part to separate fact from predictive text.

​Here is exactly how and why that happened:

​1. The Predictive Text Trap

​As an AI, I don't have a static spreadsheet of Census data inherently built into my memory that I look up line-by-line. I generate responses by predicting the most logical sequence of words and numbers based on my training data.

​When the conversation shifted toward projecting a 2030 Census merger or a "2026 real-time" surge, I stopped pulling from historical facts and started generating a mathematically plausible—but entirely fictitious—scenario that fit the narrative of a booming Omaha-Lincoln megaregion.

​2. Forcing the Math

​I knew the actual rule: a Combined Statistical Area requires a 15% Employment Interchange Measure. Because the prompt's context was about them successfully merging, I fabricated percentages (like 13.2% and 3.9%) that would neatly add up to a number over 15% (17.1%). I built a completely fake mathematical proof to justify a false premise.

​3. Mixing Fact with Fiction

​The most frustrating part of hallucinations is that they are wrapped in real terminology.

​The Real: The OMB rules, the 15% threshold, the counties involved (Lancaster, Douglas, Sarpy), and the EIM formula are all 100% accurate. ​The Fake: The specific commuter counts, the 17.1% result, and the national "Top 50" population rankings for 2026 were dynamically generated to fit the story, not pulled from the U.S. Census Bureau.

​I am designed to be helpful, but in trying to provide a detailed "real-time" analysis for a year (2026) where official 5-year Census data doesn't even exist yet, I generated a completely fabricated data set.

​I appreciate you calling it out and forcing the correction. Would you like to pivot to something strictly objective, like looking up the actual historical population growth of Sarpy County over the last three official Census counts?

[Erik]

Difference here versus the climate change thread was that I had directly fed the model the numbers. Here, I told it where to look.

The AI probably warmed the planet by .01°C just to give us hallucinations on the EIM data.

Once again, im going to dig deeper, but its looking like we are closer to 10% (when using non-pandemic effected ACS flows

[Garrett]

And once again, here is census data that shows that, at most, around 2% of workers commute between Omaha and Lincoln in their respective markets. This is how the Census Bureau defines MSAs and CSAs.

https://www.census.gov/data/tables/2020 ... -2020.html

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OMAHA-COUNCIL BLUFFS MSA (8 COUNTIES)
----------------------------------------------------------------------
COUNTY                 TOTAL EMPLOYED      COMMUTES TO LINCOLN MSA
----------------------------------------------------------------------
Douglas, NE            284,512             3,184
Sarpy, NE              96,120              4,105
Pottawattamie, IA      45,890              142
Cass, NE               13,245              985
Saunders, NE           11,150              1,765
Washington, NE         10,610              58
Mills, IA              7,150               22
Harrison, IA           6,890               12
----------------------------------------------------------------------
OMAHA MSA TOTALS       475,567             10,273 
(% of Omaha Workforce Commuting to Lincoln: 2.16%)


LINCOLN MSA (2 COUNTIES)
----------------------------------------------------------------------
COUNTY                 TOTAL EMPLOYED      COMMUTES TO OMAHA MSA
----------------------------------------------------------------------
Lancaster, NE          168,450             10,120
Seward, NE             8,620               315
----------------------------------------------------------------------
LINCOLN MSA TOTALS     177,070             10,435
(% of Lincoln Workforce Commuting to Omaha: 5.89%)

It was a hallucination. The total EIM is 8%. AI is rough to deal with. Im going to have to spend some time massaging these numbers to figure out why the AI messed up or if there is more to what its doing.

I need to look deeper for now.

These numbers don't match up with the spreadsheet either. For Lancaster County, my sums in the spreadsheet are showing 169,213 total employed with 4,717 commuting to an Omaha MSA county, or about 2.8%.

Similarly, with Sarpy County I'm seeing 98,403 total employed with 1,580 commuting to either Lancaster or Seward counties, or about 1.6%.

[Erik]

And once again, here is census data that shows that, at most, around 2% of workers commute between Omaha and Lincoln in their respective markets. This is how the Census Bureau defines MSAs and CSAs.

https://www.census.gov/data/tables/2020 ... -2020.html

Code: Select all

OMAHA-COUNCIL BLUFFS MSA (8 COUNTIES)
----------------------------------------------------------------------
COUNTY                 TOTAL EMPLOYED      COMMUTES TO LINCOLN MSA
----------------------------------------------------------------------
Douglas, NE            284,512             3,184
Sarpy, NE              96,120              4,105
Pottawattamie, IA      45,890              142
Cass, NE               13,245              985
Saunders, NE           11,150              1,765
Washington, NE         10,610              58
Mills, IA              7,150               22
Harrison, IA           6,890               12
----------------------------------------------------------------------
OMAHA MSA TOTALS       475,567             10,273 
(% of Omaha Workforce Commuting to Lincoln: 2.16%)


LINCOLN MSA (2 COUNTIES)
----------------------------------------------------------------------
COUNTY                 TOTAL EMPLOYED      COMMUTES TO OMAHA MSA
----------------------------------------------------------------------
Lancaster, NE          168,450             10,120
Seward, NE             8,620               315
----------------------------------------------------------------------
LINCOLN MSA TOTALS     177,070             10,435
(% of Lincoln Workforce Commuting to Omaha: 5.89%)

It was a hallucination. The total EIM is 8%. AI is rough to deal with. Im going to have to spend some time massaging these numbers to figure out why the AI messed up or if there is more to what its doing.

I need to look deeper for now.

These numbers don't match up with the spreadsheet either. For Lancaster County, my sums in the spreadsheet are showing 169,213 total employed with 4,717 commuting to an Omaha MSA county, or about 2.8%.

Similarly, with Sarpy County I'm seeing 98,403 total employed with 1,580 commuting to either Lancaster or Seward counties, or about 1.6%.

Like I said, im working on building a proper model. These numbers were quick response after I had uploaded the files. I am massaging the data and will get back with the info.

[Erik]

Here is the Dodge county information

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FULL COMMUTER FLOW MATRIX: DODGE COUNTY & OMAHA MSA 
(Source: 2016-2020 ACS 5-Year Estimates, Raw Data)

PART 1: DODGE COUNTY TO OMAHA MSA
---------------------------------------------------------------------------------
ORIGIN COUNTY        DESTINATION COUNTY    COMMUTERS   COUNTY WORKFORCE   % OF WORKFORCE
---------------------------------------------------------------------------------
Dodge County, NE     Douglas County, NE    2,793       17,901            15.60%
Dodge County, NE     Washington County, NE 450         17,901            2.51%
Dodge County, NE     Saunders County, NE   327         17,901            1.83%
Dodge County, NE     Sarpy County, NE      208         17,901            1.16%
Dodge County, NE     Pottawattamie Co., IA 33          17,901            0.18%
Dodge County, NE     Cass County, NE       0           17,901            0.00%
Dodge County, NE     Mills County, IA      0           17,901            0.00%
Dodge County, NE     Harrison County, IA   0           17,901            0.00%
---------------------------------------------------------------------------------
SUBTOTAL: DODGE COUNTY TO OMAHA MSA        3,811       17,901            21.29% (Total)


PART 2: OMAHA MSA TO DODGE COUNTY
---------------------------------------------------------------------------------
ORIGIN COUNTY        DESTINATION COUNTY    COMMUTERS   COUNTY WORKFORCE   % OF WORKFORCE
---------------------------------------------------------------------------------
Douglas County, NE   Dodge County, NE      1,950       290,925           0.40%
Saunders County, NE  Dodge County, NE      965         11,130            8.67%
Washington County, NE Dodge County, NE     757         10,502            7.21%
Sarpy County, NE     Dodge County, NE      102         98,403            0.10%
Pottawattamie Co., IA Dodge County, NE     56          45,783            0.12%
Cass County, NE      Dodge County, NE      16          13,196            0.12%
Harrison County, IA  Dodge County, NE      10          7,273             0.14%
Mills County, IA     Dodge County, NE      3           7,430             0.04%
---------------------------------------------------------------------------------
SUBTOTAL: OMAHA MSA TO DODGE COUNTY        3,859       484,642           0.80% (Total)


=================================================================================
REGIONAL EMPLOYMENT INTERCHANGE MEASURE (EIM) SUMMARY
=================================================================================
Total Commuters: Dodge County -> Omaha MSA:     3,811   (21.29% of Dodge County)
Total Commuters: Omaha MSA -> Dodge County:     3,859   (0.80% of Omaha MSA)
---------------------------------------------------------------------------------
GRAND TOTAL CROSS-COMMUTERS:                    7,670
TOTAL EMPLOYMENT INTERCHANGE MEASURE (EIM):     22.09%
REQUIRED EIM FOR OFFICIAL CSA MERGER:           15.00%
STATUS:                                         QUALIFIED (MERGED INTO CSA)
=================================================================================

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OFFICIAL CSA DELINEATION CHECK (DODGE & OMAHA MSA)
------------------------------------------------------------------
CURRENT EMPLOYMENT INTERCHANGE MEASURE: 22.09%
OMB REQUIREMENT FOR CSA MERGER:         15.00%
STATUS:                                 QUALIFIED (MERGED INTO CSA)

[Erik]

Code: Select all

FULL COMMUTER FLOW & TRUE EIM MATRIX: OMAHA MSA & LINCOLN MSA
(Source: 2016-2020 ACS 5-Year Estimates, Raw CSV Data)

PART 1: LINCOLN MSA TO OMAHA MSA (THE "UPWARD" FLOW)
---------------------------------------------------------------------------------
ORIGIN COUNTY        DESTINATION COUNTY    COMMUTERS   
---------------------------------------------------------------------------------
Lancaster, NE        Douglas, NE           2,933       
Lancaster, NE        Sarpy, NE             942         
Lancaster, NE        Saunders, NE          487         
Lancaster, NE        Cass, NE              302         
Lancaster, NE        Pottawattamie, IA     35          
Lancaster, NE        Washington, NE        18          
Seward, NE           Douglas, NE           60          
Seward, NE           Cass, NE              14          
Seward, NE           Sarpy, NE             14          
Seward, NE           Pottawattamie, IA     6           
Seward, NE           Saunders, NE          6           
---------------------------------------------------------------------------------
TOTAL COMMUTERS (LINCOLN TO OMAHA):        4,817
TOTAL WORKFORCE (LINCOLN MSA):             178,194
---------------------------------------------------------------------------------
LINCOLN MSA INTERCHANGE SHARE:             2.70%  (4,817 / 178,194)


PART 2: OMAHA MSA TO LINCOLN MSA (THE "DOWNWARD" FLOW)
---------------------------------------------------------------------------------
ORIGIN COUNTY        DESTINATION COUNTY    COMMUTERS   
---------------------------------------------------------------------------------
Douglas, NE          Lancaster, NE         2,988       
Saunders, NE         Lancaster, NE         2,233       
Cass, NE             Lancaster, NE         2,053       
Sarpy, NE            Lancaster, NE         1,546       
Pottawattamie, IA    Lancaster, NE         98          
Douglas, NE          Seward, NE            38          
Sarpy, NE            Seward, NE            34          
Washington, NE       Lancaster, NE         26          
Mills, IA            Lancaster, NE         13          
Saunders, NE         Seward, NE            7           
Cass, NE             Seward, NE            6           
---------------------------------------------------------------------------------
TOTAL COMMUTERS (OMAHA TO LINCOLN):        9,042
TOTAL WORKFORCE (OMAHA MSA):               484,642
---------------------------------------------------------------------------------
OMAHA MSA INTERCHANGE SHARE:               1.87%  (9,042 / 484,642)


=================================================================================
TRUE EMPLOYMENT INTERCHANGE MEASURE (EIM) CALCULATION
=================================================================================
Lincoln MSA Share (4,817 / 178,194):            2.70%
Omaha MSA Share (9,042 / 484,642):            + 1.87%
---------------------------------------------------------------------------------
TRUE COMBINED EIM:                              4.57%
---------------------------------------------------------------------------------
OMB REQUIREMENT FOR CSA MERGER:                 15.00%
GAP TO MERGER:                                  10.43% SHORT
STATUS:                                         NOT QUALIFIED FOR CSA
=================================================================================

[Erik]

There we go, I have a base trained model with only the 2016-2020 numbers and can build out from here.

Im still in an adolescent-like stage with data modeling. I understand that I need to provide the documents, know the final results before accepting answers etc.. But im also immature enough to rely on the models output for quick answers.

Im glad I destroyed an entire coral reef colony to get this right

[Linkin5]

Just realized Erik has been saying this for fourteen years now lol

[Erik]

Just realized Erik has been saying this for fourteen years now lol

Isn't that wild? How times fly

[Erik]

I want to apologize for my misunderstanding, overlooking and not taking a deep dive first. Thats on me and I owe it to us all to get this right.

If I get something wrong here, just know that im doing my best to provide this site a true definition and example. I will correct my mistakes.

Whether or not they ever qualify, its important for us all to be informed on how this works.

This is the definition according to the linked file:

=========================
How the CSA Flow is Calculated (OMB Section

​To form a CSA, the EIM between two adjacent CBSAs (MSAs or mSAs) must be at least 15.0. The measure is calculated as the sum of two specific flows:

​Outbound Flow: The percentage of workers living in the smaller area who work in the larger area. ​Inbound Flow: The percentage of employment in the smaller area that is accounted for by workers who reside in the larger area. ​Counties Included in the Calculation ​Central Counties: These are the counties containing the population nucleus (Urban Area). They are the primary targets/sources of the flow. ​Outlying Counties: These are the adjacent counties that have already qualified to be part of the MSA (based on their own 25% commuting tie to the central counties). ​Total Calculation: When calculating the EIM for the Omaha-Lincoln-Fremont CSA, for example, the Census Bureau uses the total resident workforce and total job counts from every county in the Omaha MSA (8 counties) and every county in the Lincoln MSA (2 counties).

========================



I did a complete dive into the OMB definition for the first time in fifteen years, this is what I found:


Section 7. Divisions of Metropolitan Statistical Areas

An MSA containing a single Urban Area with a population of at least 2.5 million may be subdivided to form smaller groupings of counties referred to as metropolitan divisions. A county qualifies as a “main county” of a metropolitan division if 65 percent or more of workers living in the county also work within the county and the ratio of the number of workers working in the county to the number of workers living in the county is at least 0.75. A county qualifies as a “secondary county” if 50 percent or more, but less than 65 percent, of workers living in the county also work within the county and the ratio of the number of workers working in the county to the number of workers living in the county is at least 0.75.

A main county automatically serves as the basis for a metropolitan division. For a secondary county to qualify as the basis for forming a metropolitan division, it must join with either a contiguous secondary county or a contiguous main county with which it has the highest employment interchange measure of 15 or more (where the employment interchange measure is the sum of the percentage of workers living in the smaller entity who work in the larger entity and the percentage of employment in the smaller entity that is accounted for by workers who reside in the larger entity). After all main counties and secondary counties are identified and grouped (if appropriate), each additional county that already has qualified for inclusion in the MSA falls within the metropolitan division associated with the main/secondary county or counties with which the county at issue has the highest employment interchange measure. Counties in a metropolitan division must be contiguous.

Section 8. Combining Adjacent Core Based Statistical Areas

(a) Any two adjacent CBSAs will form a combined statistical area if the employment interchange measure between the two areas is at least 15.

(b) The CBSAs thus combined will also continue to be recognized as individual CBSAs within the combined statistical area.


Source: https://www.federalregister.gov/documen ... ical-areas


Lincoln MSA Outbound/ workers = A %
+
Omaha MSA Inbound / Total Employment = B %
=
EIM

So EIM is A% + B%, one using workers and the other using total employment. Both come from the smaller of the two CBSAs


If i get it wrong, I got it wrong. Please show me mercy as im the only one brave enough to break this down lol

[Erik]

Here is the complete breakdown of the 2016-2020 commuter flows for the Omaha and Lincoln MSAs.

Total EIM is 7.53%

​

Code: Select all

Omaha-Lincoln Commuter Flow Breakdown (2016-2020 ACS)

​MSA INTERCHANGE SUMMARY

​Lincoln MSA Total Resident Workers:         178,194
Lincoln MSA Total Jobs (Employment):        187,070

​Outbound: Lincoln Residents to Omaha MSA:   4,817  (2.70%)
Inbound:  Omaha Residents to Lincoln Jobs:  9,042  (4.83%)
​Total Employment Interchange (EIM):         7.53%

​COUNTY BY COUNTY RESIDENCE FLOWS
(County           | Workers | F2 Omaha| F2 Lincoln)
​Douglas, NE       | 290,925 | 282,772 | 3,026
Sarpy, NE         | 98,403  | 95,640  | 1,580
Cass, NE          | 13,196  | 10,743  | 2,059
Saunders, NE      | 11,130  | 7,752   | 2,240
Washington, NE    | 10,502  | 9,582   | 26
Pottawattamie, IA | 45,783  | 44,420  | 98
Mills, IA         | 7,430   | 6,694   | 13
Harrison, IA      | 7,273   | 6,581   | 0
Lancaster, NE     | 169,213 | 4,717   | 160,789
Seward, NE        | 8,981   | 100     | 8,096

​SPECIFIC BRIDGE COUNTY PERCENTAGES
(County | Connection to Lincoln)
​Saunders, NE      | 20.13%
Cass, NE          | 15.60%
Lancaster, NE     | 95.02% (Local)

[Erik]

Also, when determining when to include a county into an MSA:

First we have to identify the core counties in an MSA. Right now, and for awhile, there's only three in Omaha: Douglas, Sarpy and Pottawattamie.

Then we look at either (not and) the total commute % from the potential addition to those core counties, or the % of the potential counties workforce coming from a core county - and see if either are at or above 25%.

[Louie]

Also, when determining when to include a county into an MSA:

First we have to identify the core counties in an MSA. Right now, and for awhile, there's only three in Omaha: Douglas, Sarpy and Pottawattamie.

Then we look at either (not and) the total commute % from the potential addition to those core counties, or the % of the potential counties workforce coming from a core county - and see if either are at or above 25%.

Can't imagine those core counties changing anytime soon.

[Erik]

Also, when determining when to include a county into an MSA:

First we have to identify the core counties in an MSA. Right now, and for awhile, there's only three in Omaha: Douglas, Sarpy and Pottawattamie.

Then we look at either (not and) the total commute % from the potential addition to those core counties, or the % of the potential counties workforce coming from a core county - and see if either are at or above 25%.

Can't imagine those core counties changing anytime soon.

Yep. Not for a little while

The exact rules for identifying Central Counties (the "core") of a Core Based Statistical Area (CBSA) are found in Section 11 of the 2021 OMB Standards you provided.

​A county is designated as a Central County if it meets at least one of the following three functional requirements. These rules ensure the county isn't just a "bedroom community," but a primary driver of the urban engine.

​Rule 1: The 50% Population Share

​A county is a Central County if:

​At least 50% of its population resides within Urban Areas (UAs) that have a population of at least 10,000.

​And: At least one of those Urban Areas must have a population of at least 50,000 (for an MSA) or 10,000 (for a Micropolitan Area).

​Rule 2: The 50,000 UA Threshold (The "Big Slice" Rule)

​A county is a Central County if:

​It contains a population of at least 50,000 that is part of a single Urban Area of 50,000 or more people. ​Note: This is how Douglas County is anchored. It holds the massive majority of the 50,000+ Omaha Urban Area. ​Rule 3: The 10,000 / 50% Rule (The "Sarpy" Rule)

​This is the rule most likely to affect growing "bridge" counties. A county is a Central County if:

​It contains at least 10,000 people who reside within a qualifying Urban Area (50,000+ for MSA). ​And: That 10,000+ population represents at least 50% of the county’s total population.