Over the past several decades, the U.S. Census Bureau has employed a straightforward, consistent methodology for counting and collecting data on the people living in the U.S. The data collected on individuals includes a wide variety of elements like age, gender, marital status, household income, presence of children and commuting patterns. In turn, both the public and private sectors use this data in order to make decisions regarding everything from grant money allocation to retail store location placement to marketing.

Census methodology in the recent past has utilized a “Short Form” which is required to be completed by all residents in the United States. The short form captured a count of the population and the number of households, along with demographic information like age, gender, race, ethnicity, and marital status. Since 1940, the Census Bureau also has used a “Long Form” which was distributed to 1 in 6 households to capture more specific data. The long form was quite involved, and captured data on housing values, rents, types of facilities in the household, information on employment and wages, transportation, and dozens of other items. This form included questions about everything, even the kitchen sink!

In 2000, approximately 18 million households were tapped for the Long Form data collection. This information was used to create estimates for the key indicators that it captured and has been updated through statistical estimation procedures and other data throughout the last decade. However, given that the Census data was collected in 2000, it is extremely out of date as we enter 2010. Late in the 20th Century, the population of the U.S. began changing so rapidly that the old way of capturing these important data every 10 years was no longer reflecting the U.S. population accurately. In fact, by the year 2000, trends that were anticipated for the year 2040 based on the 1990 Census and trends from previous decades had already happened. That is, projections that were anticipated to take 50 years to occur based on historical trend data from the decennial Census, actually occurred within a decade. The Long Form/Short Form decennial data collection method needed changes to capture these trends in an increasingly dynamic U.S. population.

In 2010 this Long Form/Short Form methodology for collecting data on the U.S. population is being replaced. The Short Form will be distributed to every household in the U.S., just as it has been. And, the Long Form will be taking its place in the history books. It will no longer be used.

At Buxton, the data supplied by or developed based on the U.S. Census is considered in nearly every project we complete for our clients. As a partner to over 1,900 retailers, restaurants, city governments, healthcare providers and consumer packaged goods manufacturers, we have completed our own research of the changes that the Census Bureau has slated for the 2010 Census to fully understand how the data that we use in our projects will be impacted. How will the changes to the data collection of the U.S. Census impact us? We may not need the data on the kitchen sink, but information about commuting patterns, education, languages spoken, income, ages of homes, values of homes and rents as examples can be very important to our clients’ decisions.

The data that was typically collected using the Census Long Form will now be captured by the American Community Survey (ACS). There are two key differences between the Long Form approach and the ACS. First, the ACS uses a form that is sent to a statistically-controlled sample of approximately 3 million households per year to capture data on many of the same topics that the Census Long Form captured. Second, the ACS is completed every year, as opposed to the Census Long Form being completed every 10 years. The trade off is that there are fewer households completing the ACS in a given year than there were completing the Census Long Form, but that there are no gaps between data collection periods. Given these changes, the ACS approach of collecting smaller slices of data on an annual basis from a smaller sample is more likely to capture changes in the population as they occur.

These smaller samples of the population captured by the ACS do provide reliable large-scale population data every year. In fact, areas that have a population exceeding 65,000 will see fully updated data estimates from the Census Bureau annually. However, smaller scale areas typically used in more granular analysis such as local area marketing or location analysis for retailers, restaurants and healthcare providers will see updates from the Census Bureau on a rolling feed. It takes 5 years worth of ACS survey captures in order to have a sample large enough to create an estimate for these more granular areas. These smaller areas will see updates once a year, but they will be based on 5 years worth of data. In short, the small area estimates released in 2010 for the ACS will actually be based on data collected from 2005 to 2009.The precision of taking estimates in a single year is being traded for more frequently updated, longer term data collections.

Impacts on the data that Buxton uses:

Overall, the ACS offers at least two advantages for the data that Buxton uses in our models, products and services:

1. The data collected by the ACS is captured by U.S. Census Bureau staff dedicated to this survey. The Census Long Form was deployed primarily with temporary staff, hired only once a decade. These relatively untrained agents offered a risk for error in the data collection. With the ACS, the agents involved in data collection are dedicated to the ACS on a permanent basis. Using a trained and dedicated staff for the data collection will lead to a more consistent data collection process and more reliable data in the end.
2. The data supplied through the ACS will never be more than 5 years old. The ACS gathers enough information to provide population and population characteristic estimates for even the smallest of Census areas (i.e., block groups of about 400 households) every 5 years.

There will certainly be changes to the data that Buxton uses, but based on the changes to the Census, we are expecting them to be for the better. At Buxton we have several data providers in place that support our clients’ needs. Specifically, Buxton clients should rest assured in the fact that:

1. Buxton’s providers for U.S. Census data estimates and projections have been using the ACS data to enhance their population estimates and projections for several years. They have experience with the ACS data as an alternative to the Census Long Form data and have developed sound methodologies for the use of the ACS to estimate and describe the populations of very granular areas. 
2. Buxton relies heavily on other sources of data including household-level data that is updated on a daily, not an annual basis. The household level data that we use in our analyses is compiled from approximately 3,200 public and private sources, only one of which is the U.S. Census. We receive refreshed downloads of this up-to-date data at our Texas headquarters every 8 weeks.
3. As a data consumer, not a data provider, Buxton is committed to having best-in-class data available to solve our clients’ business problems. We continue to vet all of our data sources to ensure that data quality is consistent or improved regardless of changes to methodology for data collection.

View the Winter 2010 Buxton Fast Facts Newsletter