We now have a new database for CDXZipStream that provides an extensive variety of demographic data for 2010 census tracts. CDXZipStream is our Excel-based zip code software that performs address, zip code, and geographic analysis, including route optimization, geocoding, zip code radius calculations, address verification, and demographics import.

Demographics based on census tract offers significant advantages over zip code data. Since census tracts are about half the population of zip code areas, the smaller size provides a more accurate demographic snapshot.  Also, zip code census data is actually based on ZCTA's, or Zip Code Tabulation Areas, which the Census Bureau use to approximate zip codes. Census tracts, which are precisely defined by the Census Bureau, do not include the possible error associated with using ZCTA's.

The CDXTract feed provides a variety of data from the 2010 Census and the on-going American Community Survey.  Topics are:

- Age

- Individual Earnings

- Educational Attainment

- Household Size

- Household Income

- Housing Value and Rent

- Marital Status

- Population

- Race

- School Enrollment

- Land, Water Area

For a complete listing and description of each demographic variable, you can download an Excel file which describes each CDXZipStream data feed in detail, including CDXTract.

To access the data, census tract codes (also referred to as FIPS codes), must be provided as input in an Excel worksheet. CDX Technologies now offers a free Excel template that can identify census tract codes for an address list – please see our blog posting Get Census Tract FIPS Codes in an Excel Template.  You can also view a short Youtube tutorial on how to use the template: Get Census Tract FIPS Codes in Microsoft Excel.

Once you have the list of FIPS codes for each location, use your cursor to select the first code in your list, then click on the CDXZipStream icon on the main toolbar. You’ll see a dialog like this:

We’ve selected the CDXTract data feed (under the Select Data Feed option), and have also added the data fields we need to the list on the right, in this case covering median age data and earnings levels.

Click "Get Data", and the selected data will now be automatically returned to the worksheet (only part of the returned data is shown here):

For a short tutorial on how to use the CDXTract data feed, please see the YouTube video Census Tract Demographics for an Address List.

Between the recent 2010 Census and the ongoing American Community Survey, there is now an unprecedented level of extensive, up-to-date demographics data available for the U.S. market.  Please note that census tract data is an additional purchase, and is compatible with all demographic versions of CDXZipStream.  For pricing information and access to the CDXTract database, please contact us at 1-877-CDX-TEC1 (1-877-239-8321) or support@CDXTech.com.

In our Microsoft Excel add-in, CDXZipStream, there are three data feeds (CDXState, CDXCounty, and CDXCBSA) that provide population estimates for their respective geographies for each of the past ten years.  (These data feeds are available in the CDXZipStream Premium and Premium ACS versions.)   These population estimates are developed by the U.S. Census Bureau, and the entire time series of estimates beginning with the most recent decennial census is revised annually. Ultimately these provide an extremely accurate historical picture of population growth trends over the previous decade, a very useful piece of information for many industries ranging from home construction to car sales.

To access these population estimates within Microsoft Excel, select the first worksheet cell that starts your list of geographic locations.  For instance, here is a list of counties in an Excel workbook:

When working with county lists, use the format "County|State", where a vertical bar delimiter is used to separate the county name and state two-letter abbreviation.  When working with state lists, you must also use the state two-letter abbreviation.  For Core-Based Statistical Areas (CBSA’s) use the five-digit designation by the Office of Management and Budget, which can be found on the census website.   For instance, the Akron, Ohio CBSA has the five-digit designation 10420.

After selecting the first cell in the list, click on the CDXZipStream button on the main toolbar, and on the main dialog select the appropriate feed (in this case, CDXCounty) and desired years of estimated data:

Click “Get Data” and the requested data for the last ten years is returned to the worksheet (only partial data is shown here):

You can now use Excel’s calculational and charting capabilities to look for population trends.  For instance, do you need to locate a franchise to take advantage of high population growth within a particular county, state, or CBSA?  The combination of CDXZipStream and Microsoft Excel can quickly help you quantify trends that will allow you to make decisions based on hard, accurate data. 

We’ve just added a new free CDXZipStream template, downloadable from our website, which identifies census tract FIPS codes for a list of address locations.  CDXZipStream is our Microsoft Excel add-in that performs address, zip code, and geographic analysis, including route optimization, geocoding, zip code radius calculations, and address verification.

A FIPS code is a unique 11-digit code assigned to each census tract by the U.S. Census Bureau, and identifying the FIPS code for a given address allows us to tap into the wealth of demographic information available from surveys such as the ten-year U.S. Census and annual American Community Survey.  Since census tracts are on average only about half the size of zip code areas, they provide a much more accurate demographic picture of the population surrounding a given address.  For more information about FIPS, please refer to our recent blog post All About FIPS Codes.

To use the template:  You will need to install CDXZipStream (MapPoint version or higher), Microsoft MapPoint, and also have access to an internet connection.  The template is also compatible with both trial versions of CDXZipStream and MapPoint.   Just copy and paste your list of addresses to the template, and press the button “Get FIPS”.  CDXZipStream works with Microsoft MapPoint to geocode each address (get its latitude and longitude); this data is then used to pinpoint the specific census tract where each address is located, using an FCC application programming interface.  Currently the template is limited to identifying FIPS codes for a maximum of 5000 addresses at a time.  If necessary you can run the template more than once if you have more than 5000 addresses to analyze.

Since CDXZipStream looks to match each listed address to a location in MapPoint, the match quality is also evaluated.  Match types are:

1. Exact - A unique entry was found in MapPoint for this address.

2. Allow Ambiguous - The first of at least two matching entries was found in MapPoint.

3. Best Match - MapPoint did not find a good match, but here is the best of possible alternatives.

4. Zip Code - MapPoint could not find any matches, the centroid of the zip code is returned from CDXZipStream

Since only match types Exact and Allow Ambiguous represent good matches, FIPS codes are only returned for these types.  Address information for other matches should be checked for misspellings, zip code mismatches, or other errors.  Consequently the template provides a method for address verification along with FIPS census tract identification.

We will soon be introducing new functionality to CDXZipStream that takes advantage of a unique code assigned to all geographic areas by the U.S. Census Bureau, called the FIPS (Federal Information Processing Standard) code.  CDXZipStream is our Microsoft Excel add-in that performs location analysis for address lists, such as route optimization, zip code radius calculation, and demographics retrieval. 

FIPS codes can be used to accurately identify very small geographies, such as census tract and block areas, and subsequently allow us to retrieve a wealth of demographic, economic, and cultural data from Census Bureau surveys, such as the ten year 2010 Census and American Community surveys.  A major advantage is that both census tracts and blocks are smaller than zip code areas; zip codes on average cover a population of over 9,000, while census tracts are about half that size and census blocks only cover a population of about 100.  As a result, the demographic data for these smaller geographies can provide a much more accurate picture of the population. 

Also, census tracts and blocks are assigned by the Census Bureau, and census data for these areas are fairly precise.   Zip codes are assigned by the U.S. Postal Service, are modified frequently, and must be approximated when applying census data by using ZCTA’s (Zip Code Tabulation Areas).  ZCTA’s are the Census Bureau’s approximate definition of a zip code area that is obtained by aggregating data of census blocks that cover a similar area.  This approximation can introduce additional error in the resulting data.

So what does a FIPS code look like?  For the smallest block geography, it is a 15-digit code that progressively builds upon FIPS codes for state, county, and census tract.  Here’s an example of a block FIPS code for the address 1600 Pennsylvania Avenue, Washington DC :

The FIPS code for the census tract for this address is the first 11-digits (minus the block number), or 11001006202.  Note that when the census tract number is used alone, it will often contain a decimal point, such as 0062.02.  The decimal point is always excluded from the FIPS code.

With the recent 2010 Census and the ongoing American Community Survey, there is now an unprecedented source of extensive, up-to-date demographics data available from the U.S. Census Bureau.   FIPS codes are a very useful key to access this data down to the address level. 

For more information about Census geography, please refer to the following posts:

Census Geography - It's Not Quite What You Learned in School

What's a ZCTA?

Our Microsoft Excel add-in CDXZipStream has several demographic versions that provide extensive data from the 2010 Census and recent American Community surveys.  CDXZipStream is especially well-suited for quickly and easily obtaining demographics for long lists of zip codes, cities, counties, states, and other geographies.  For more information please refer to this comparison of CDXZipStream demographic versions as well as the data fields listing for each provided data feed.

There may be situations, however, where you need data for a single address or geographic area, and the particular demographic variable required is not offered by CDXZipStream.  For these cases we’d like to recommend a handy little tool provided courtesy of the U.S. Census Bureau.  It’s called American Factfinder, and it was redesigned last year to provide the most up-to-date online facility for getting census data.  It can be a goldmine of information but is not necessarily intuitive for the average user, so let’s walk through getting some demographic data around a specific street address.

First, go to the American Factfinder2 main page and click on “street address” in the Address Search area:

A dialog box will appear where you can input the address of interest. Then click “Go” and you’ll see a menu selection that will allow you to choose the geographic type: 

Geography types include state, county, county subdivision, block census tract, etc.  For this example we require data for the entire census tract that contains this address, so we click on the left-hand column selection (in blue) Census Tract 1002, Lackawanna County, Pennsylvania.  (For data for the entire zip code, you would need to select ZCTAS 18503.  ZCTA, or Zip Code Tabulation Area, is the Census Bureau’s approximation of a zip code area.)  The census tract now shows up in the “Your Selections” display in the upper-left hand corner of the screen:

You can repeat this process for more addresses, and can even mix-and-match different geography types in your selections.  

Now let’s move on to selection of the data type.  If necessary, close the “Geography Results” box by clicking on “Close” in the upper right hand corner.  You should see a list of search results showing “Tables, Files, and Document Names” that all contain data for this particular census tract:

What’s shown in this list is dependent upon the geographic selection made in the previous step.  For example, census tract data is available from both the latest American Community Survey (ACS) 5-year results, and the 2010 Census, shown here as 2010 SF1 and 2010 SF2.  However, census tract data is not available from the more recent ACS 1-year results, since census tract areas are not large enough provide statistically significant data over a 1-year sample period.  Therefore, the availability of data will vary as a function of geographic type.

Assuming we don’t quite know which table we need yet, let’s narrow our search by inputting some relevant keyword(s).  The keyword “income”brings up some specific tables and areas of interest; we click on Income/Earnings for Individuals:

... and another listing of tables appears:

If our interest is income for the foreign born population, we select the box for table B06010 (Place of Birth by Individual Income ….).  Up to ten difference tables can be selected in a single download.  We can then either select “View” to see the data online, or “Download” to obtain the data file.  These files are provided in .csv format that can be opened and viewed using Microsoft Excel or Access.  

If you don’t like the search results or need to use another keyword, make sure to delete the previous search selection in the “Your Selections” box in the upper left-hand corner.  It is also sometimes helpful to view some of the larger tables (covering topics such as Population, Economics, Social, and Housing characteristics) to get a sense of the kind of data available.  These larger tables generally cover a large majority of the more interesting topics.

AmericanFactfinder2 is an excellent source of data that is well-suited for finding demographics for a specific address.  When CDXZipstream is not a good fit, try American Factfinder as just one more tool that can support your business needs.

The U.S. Census Bureau has recently released the Census 2010 Summary File (SF-1) that includes a compilation of the data by Zip Code Tabulation Areas (ZCTAs).  ZCTAs are an approximation of the U.S. Postal Service zip codes and are actually aggregates of small census-defined areas called blocks.  Since ZCTAs generally match zip code areas very closely, for the purposes of this article we will use the terms ZCTA and zip code interchangeably.  For more information on ZCTAs, please see our blog posting “What’s a ZCTA?”  

Zip code data is especially valuable for market research, target marketing, and sales planning, since zip codes represent a fairly small (on average zip codes cover about 9,400 people) homogenous area that can be matched to readily available mailing address lists.  And since the decennial census is a 100% count of the population, census data provides a truly complete snapshot of the American population as a whole. 

To see the data from the new Summary File, go to the on-line American Factfinder tool and select the 2010 SF1 100% Data Set under Topics.  You can then select ZIP code/ZCTA as a geographic filter and find the specific geography and data table of interest.  For a list of zip codes more typical of a customer mailing list, however, it is easier to use our software CDXZipStream which has a selection of the more important demographic variables from the 2010 Census.  These variables, covering age, population, households, and race data, are: 

1. Population

2. MalePopulation

3. FemalePopulation

4. MedianAge

5. MedianAgeMale

6. MediaAgeFemale

7. HouseholdsPerZipcode

8. PersonsPerHousehold

9. AsianPopulation

10. BlackPopulation

11. HawaiianPopulation

12. HispanicPopulation

13. OtherPopulation

14. IndianPopulation

15. WhitePopulation

These are part of the Premium Zip Code data feed, available with the Demographic, Premium, and Premium ACS versions of our Excel add-in software CDXZipStream.  Please see the version comparison webpage for more information on other features of these versions.

To obtain data for these fields for a list of zip codes in Microsoft Excel, place your cursor on the first zip code and click on the CDXZipStream logo on the main toolbar.  Just select the fields of interest, and click “Get Data”.  The data is returned (with optional field headings) like this:

You can also view the YouTube Video “Demographic Data in Excel” for a quick demonstration of how to get demographics for long zip code lists using this method.

CDXZipStream offers hundreds of demographic variables based on zip code, city, state, and other geographic entities.  It’s also a very easy software to use since it works entirely within Microsoft Excel, and is a very economical alternative to much more expensive data sources. To help our clients decide which version of CDXZipStream can best meet their demographic needs, we’d like to review all of its data feeds that provide the most useful economic indicators (such as household income and housing value) that our clients typically ask for.

There are three versions of CDXZipStream that include demographic data feeds from the ten-year census, American Community Survey, Economic Census, and other sources.  These are best described in terms of the data feed types that are included in each version: 

CDXZipStream Demographic:  Data Feed Type1

CDXZipStream Premium:  Data Feeds Type 1, 2, and 3

CDXZipStream ACS Premium:  Data Feeds Type 1, 2, 3, and 4

The economic-related data fields included in each feed are as follows:  (Keep in mind that other non-economic demographic data are also available from these feeds, please download the complete list of all fields.)

Data Feed Type 1 (CDXZipCode Premium):  Average house value, income per household from Census 2000.  Data are provided by zip code.

Data Feed Type 2 (CDXCity, CDXCounty, CDXState, CDXAreaCode, CDXCBSA):  Average house value, income per household from Census 2000.  Data are provided by city, county, state, area code and Core-Based Statistical Area.

Data Feed Type 3 (CDXCensus):  Detailed individual earnings, household income, housing value and rent from Census 2000.  Data are provided by zip code.  

The specific data fields for CDXCensus are:

Data Feed Type 4 (CDXACSPlace, CDXACSCounty, CDXACSState, CDXACSCBSA):  Detailed individual earnings, household income, housing value and rent averaged over the last five years of data from the American Community Survey, administered by the U.S. Census Bureau.  Data are provided by city (also called “place” by the Census ), county, state, and Core-Based Statistical Area.  The specific data fields are:

We will soon be introducing in December 2011 additional zip code data feeds with economic indicators from the most recent American Community Survey.   Stay tuned! 

Data from the U.S. Census Bureau is an indispensible source of demographic information that helps businesses, non-profits, and even the smallest mom-and-pop store plan, market, and ultimately reach their target audience.  But there are limitations to the data, particularly for smaller geographies, that should be considered before making any critical demographics-related decisions.

Since participation rates for census surveys are never 100%, there will always be some error associated with demographics estimates.  For example, the American Community Survey samples about 2% of American households every year, and the accuracy of the estimates can vary significantly, especially for geographic areas where populations are small and sampling error can be large.  Here are some results from the latest 5-year data set from the ACS covering the years 2005-2009:

The error results for the American Community Survey are all for 90% margin of error, meaning that there is 90% confidence that the true result lies within the margin of error around the estimate.  For instance, for Albany County, there is 90% confidence that the median income is $55,350 plus or minus $1,061; this means the actual 90% confidence range is $54,289 - $56,411.  Even with this level of error, however, the median income estimates for Albany County, Albany city, and Census Tract 2 are significantly different from a statistical point of view, since there is no overlap when including the margin of error for each estimate. 

In the case below, involving all small census tract geographies, the picture is not so clear:

Since the margin of error is so large for Census Tract 4.01, we cannot be confident that the true median income is statistically different from Census Tract 1.  The estimate ranges, including the margin of error, overlap for Census Tracts 1 and 4.01, even though the estimate values ($37,619 versus $62,039) are quite different. We can say with confidence, however, that the median income for Census Tract 2 is statistically different from Census Tract 4.01 since the estimate ranges do not overlap.  It certainly helps in this case that the margin of error for Census tract 2 is relatively small for this geography.

It's easy to cherry-pick data like this to show how the margin of error effects how we interpret the results, but the fact remains that survey error can be an important part of data interpretation particularly for cases where the error is large.  When important decisions need to be made based on demographics, margin of error should always be part of the analysis.

Demographic data as provided in our products CDXZipStream and CDXStreamer is based on various census geographies.  But what do we really mean here by "geography"?  It's really just the way the U.S. Census defines a geographic area in the United States, and many census geographies, such as states and counties, we're already pretty familiar with.  However, have you ever heard of a Census Designated Place, or CDP?  How about a Core-Based Statistical Area, or CBSA?  If you're interested in using demographic data to find a location for your business, design a marketing program, or even perform academic research, you may find these less well-known geographies useful.

The most basic census geography is the census block, which is well-named since it is the building block for just about all other geographies.  For the 2010 census there are over 11 million census blocks covering the U.S., the District of Columbia, and Puerto Rico.  Since it is the smallest geography, census blocks can be grouped together to form larger geographies such as counties, states, and regions.  Here's a helpful diagram provided by the Census Bureau, with the smallest geographies at the bottom, and the largest geographies at the top:

Census blocks are typically defined by physical features like roads or rivers, and other boundaries such as city limits or property lines.  They can correspond to individual city blocks, but in rural areas may cover much larger areas.  Population is also a factor; the average size nationally of a census block is about 100 people.

Here are some other census-specific geographies of interest:

Census tracts are geographic units representing urban or rural neighborhood-like communities, and are made up of adjoining census blocks.  Census tracts, like blocks, usually coincide with the limits of cities, towns or other administrative areas, and several tracts commonly exist within a county. There are just over 66,000 census tracts covering the U.S., with an average population of about 4,000.  Census tracts can be extremely useful for demographic analysis since they are fairly stable, well-defined entities that are large enough to get statistically-significant data, but small enough to see a unique picture of the community.

Places are a catch-all geography that lumps together a wide variety of communities such as cities, towns, boroughs, townships, villages, and municipalities. This category also includes CDP's  (Census Designated Places) which are populated communities that do not have a local government and are not incorporated. Examples include small rural areas and unincoporated retirement communities.  Using census data for "places" can be particularly useful for smaller communities where the population is fairly homogenous, but for large cities such as New York, demographics by place can provide only a limited picture of a very diverse population.

Core-Based Statistical Areas are urban areas with a population of at least 10,000. CBSA's are defined by the U.S. Office of Management and Budget, and are determined more by social and economic ties within an area, rather than physical or political boundaries.  As a result, they can cover multiple counties, cities, and even states.  There are currently 955 CBSA's in the U.S., which are grouped according to population.  An area with a population between 10,000 and 50,000 is a Micropolitan Statistical Area, and an area with a population greater than 50,000 is a Metropolitan Statistical Area.   Since CBSA's are a truly functional geography that reflect where people live and work, they can provide a very unique demographic perspective on the area.

Zip Code Tabulation Areas, or ZCTA's, are the Census Bureau's version of zip codes, and were first developed for tabulating Census 2000 data.  ZCTA's approximate zip code areas by aggregating census blocks.  But since zip  codes as defined by the U.S. Postal Service are ever-changing and do not follow census boundaries, there will always be some discrepencies between the two.  ZCTA's of course are extremely useful since they can easily be linked to a mailing address, but it should be recognized that ZCTA's and zip codes are not exactly the same thing.  One of our recent blog posts reviews ZCTA's in more detail.

For more information about census geographies, here are some good resources:

Reference Resources for Understanding Census Bureau Geography

Census Bureau Geography

Metropolitan and Micropolitan Statistical Areas

Zip Code Tabulation Areas

In a previous post we talked about how the results of the 5-year (2005-2009) American Community Survey, released in December 2010, would provide demographics down to the zip code level for the first time.  Unfortunately, the Census Bureau did not provide zip code data with the current data release, and won't be including it for some time, at least until 2012-2013.

Zip codes, as defined by the U.S. Postal Service, are not actually a "geography" included in Census Bureau surveys.  Realizing there is significant interest in zip code demographics, the Census Bureau did provide Census 2000 data by "ZCTA" (Zip Code Tabulation Area), which required grouping data from small census "blocks" in order to approximate an actual zip code.  You can see how ZCTA's and zip codes compare in these example maps of Washington state. (Also see our previous blog post with a more detailed ZCTA description.)

Since zip codes frequently change in definition and area, the Census Bureau must now update ten-year old ZCTA definitions.  This is a complex task that was not completed in time for this first 5-year data release.  In the meantime, we at CDX Technologies are evaluating other options for providing ACS data in smaller geographies.  (We currently provide state, county, CBSA (Core-Based Statistical Area) and city data in our CDXZipStream ACS data feed.)  We'll keep you posted as our work proceeds.