You need to use PUMA (public use microdata area). You can cross reference the PUMA with a county map. In some cases, you can use one PUMA or combine several PUMAs to get a full county or an approximation. In mainly nonmetro areas you will have several counties included in one PUMA. On 7/11/2013 10:49 AM, Ben Silverman wrote: -- Michael E. Cline, PhD Associate Director Hobby Center for the Study of Texas Rice University 5615 Kirby Dr Ste 840 Houston, TX 77005 713-348-5396 Mailing Address: 6100 Main St,MS-202 Houston, TX 77005 http://hobbycenter.rice.edu

Ben, in the PUMS files, the sub-state geography is a Public Use Microdata Area (PUMA). These are geographic areas designed by the state (usually the State Data Center) and must have at least 100,000 population. I don't know about NY, NJ or CT but here in California we nested our PUMAs by county where possible. You didn't say, but I'm assuming you are using the 2000 5% PUMS. You can find PUMA maps at http://www.census.gov/geo/maps-data/maps/reference.html And detailed equivalency files at http://www2.census.gov/census_2000/datasets/PUMS/FivePercent/ Go to the folder for each of the three states and download the file that starts with "PUMEQ5-**.TXT" where ** is the state abbreviation. Because you are using records from three state, I would suggest that you create a field that is the combination of the state code and the PUMA code just in case these same PUMA code is used in more than one state. Nancy Gemignani California State Census Data Center Demographic Research Unit (916) 327-0103 ext 2550 -----Original Message----- From: ctpp-news-bounces(a)chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Ben Silverman Sent: Thursday, July 11, 2013 8:50 AM To: ctpp-news(a)chrispy.net Subject: [CTPP] Question about 2000 Census Income data I am attempting to to calculate the percentage distribution of income by quintile in 2000 for a number of counties in and around NYC. I was attempting to use the the PUM files I found here http://www2.census.gov/acs/downloads/pums/2000/ to do so, and was able to use them to calculate those quintile percentages for the states of NY, NJ and CT as a whole, but I couldn't figure out how to separate out the data in them by counties or any other geographic sub-division. Is there a way to separate the data in those files by county or other regions, or are their other files I need in order to do so and where could I find them? -Ben Silverman Regional Plan Association _______________________________________________ ctpp-news mailing list ctpp-news(a)ryoko.chrispy.net http://ryoko.chrispy.net/mailman/listinfo/ctpp-news