Skip Main Navigation Skip To Navigation Content

Office of the Small Business Ombudsman

Skip top of page navigation
You are here: Census.govOffice of the Small Business OmbudsmanSmall Business Resources › Comparing Data

Comparing Data

Most users are not just interested in what the statistics look like for a topic right now; they want to compare them with data from the past. Well, there are many variables one must consider when comparing data over time. Some of these differences include:

  • Changes in the survey/sample size or universe
  • Changes in the forms or mediums used to collect data
  • New decisions on how to tabulate data
  • New questions or a new order to old questions
  • Various geographies change over time (towns expand and contract, etc.)

For example, when comparing data from one decennial census to the next, such as Census 2010 to the 2000 Census there are several differences that stand out right away:

  • Census 2010 allowed responders to mark more than one race for the first time resulting in over 126 different racial/ethnic group combinations
  • Census blocks (lowest level of geography available) were completely renumbered and switched from three digits to four digits

[PDF] or PDF denotes a file in Adobe’s Portable Document Format. To view the file, you will need the Adobe® Reader® Off Site available free from Adobe.
[Excel] or the letters [xls] indicate a document is in the Microsoft® Excel® Spreadsheet Format (XLS). To view the file, you will need the Microsoft® Excel® Viewer Off Site available for free from Microsoft®.
This symbol Off Site indicates a link to a non-government web site. Our linking to these sites does not constitute an endorsement of any products, services or the information found on them. Once you link to another site you are subject to the policies of the new site.
Source: U.S. Census Bureau | Small Business Ombudsman's Office | (866) 564-5431 | | Last Revised: December 02, 2010