ACS Data Users Group

Hi!

So I am not american and I'm trying to understand how the american census type data from the ACS works (total newbie about it). I pulled the 2017 ACS 1-year estimate for the whole US.

But I am specifically interested in the Greater Boston Metropolitan Statistical Area (MSA) (or the Boston–Cambridge–Newton, MA–NH MSA). Now I would like to know what are the PUMAs (Public Use Microdata Areas) for this specific MSA so I can extract only data for this region from the dataset. My problem is I am unable to find that information anywhere.

I can find the names of the counties that are part of the MSA on wikipedia and try to get the list of PUMAs from this names reference PDF:

https://www2.census.gov/geo/pdfs/reference/puma/2010_PUMA_Names.pdf?# (page 20)

But a lot of the names in there are ambiguous and I would prefer to have an official list than guessing from a wikipedia page. I was able to find a list of FIPS place codes for the Greater Boston MSA, but as I understand it FIPS and PUMAs are not convertible into each other.

It looks like this website manages to do it though:

https://censusreporter.org/profiles/31000US14460-boston-cambridge-newton-ma-nh-metro-area/

So I assume this information is out there somewhere.

Is there a list somewhere of what PUMAs are in the Greater Boston MSA?

Thank you very much for your help!

Jean-Baptiste.

Jean-Baptiste

I am a planner with Cambridge, MA, one of the cities in the Boston Metro region. Information on PUMA boundaries and which PUMAs are included in a region is harder to locate than you would expect.

One trick you can use is to go to the IPUMS USA website, which is a University of Minnesota program that enables on-line analysis of PUMS data.

https://usa.ipums.org/usa/index.shtml

You will need to set up an account to use the on-line analysis tools.

You can run a simple analysis on IPUMS USA that generates a list of Boston MSA PUMAs as a byproduct. For example, if you filter for the Boston MSA using msa2013(14460) and ask for a count of all cases by PUMA by sex you will get a list of PUMAs. (I am trying to upload the list as a file to the ACS Data users Group but am running into problems.) I can tell this is likely the correct list by comparing the sum of PUMA populations to the ACS population for the region.

One thing to be aware of is that PUMAs were renumbered following the 2010 US Census. I believe that ACS data issued prior to 2012 use the older different numbering system and data sets that cross that date use both sets of PUMA numbers. For example, Cambridge, MA is now PUMA 0506 and previously was PUMA 3200. I also believe that PUMA numbers can be repeated between states, but I could be wrong about this.

You can find PUMA reference maps here:

https://www.census.gov/geographies/reference-maps/2010/geo/2010-pumas.html

Note that the Boston MSA extends into New Hampshire. You can see a map of MSAs here:

https://www2.census.gov/geo/maps/metroarea/us_wall/Sep2018/CBSA_WallMap_Sep2018.pdf?#

I hope this is helpful.

Hi Jean-Baptiste -

I agree with Cliff's suggestions.

I would also add: If you are looking for just a list of PUMAs, you may want to try the Geocorr application
mcdc.missouri.edu/.../geocorr2014.html

You can select a source geography (like PUMA) and a target geography (like Boston MSA) and the program generates a list, along with allocation factors (percent of the source geography that's in the target geography). I like to run the table with both allocation factor and "afact2" (which is % of target geography that's in the source geography) because it helps me understand how the geographies intersect one another.

As Cliff mentioned, PUMAs change every decade, so you'll want to be sure to generate a list specific to the year you are interested in (other geocorr years can be found at mcdc.missouri.edu/.../geocorr.html)

Beth Jarosz
PRB

Great thank you so much! I managed to get exactly the list that I wanted and those allocation factors are also really helpful.

For anyone interested, I used the 2012 PUMAs as source and 2015 CBSA as a target, for the states of MA and NH.

Jean-Baptiste.