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Data Protection and Privacy Policy

Web Measurement and Customization Technologies

We use web measurement and customization technologies to optimize your experience during your visit to our websites and to provide statistically accurate data about how you use our website. These technologies are commonly known as "cookies," and may include the use of persistent cookies and other web measurement and customization technologies.

There are three "tiers" of these web measurement and customization technologies, as established by the Office of Management and Budget (OMB):

Tier 1 - Single Session

This technology tracks the user's online interactions within a single session or visit to a single website. Any information related to a particular visit to the website is deleted from the user's computer immediately after the session ends.

Tier 2 - Multi Session without Personally Identifiable Information

This technology notices when a user returns to a website and remembers his or her online interactions and preferences across multiple sessions, typically for the purpose of web analytics, but also for customizing people's online experience.

Tier 3 - Multi Session with Personally Identifiable Information

This technology is the same as Tier 2, but ties a tracking mechanism to the user's personally identifiable information.

The following sections include information describing the use of these tiers when you visit Census Bureau websites.

Use of Tiers When You Visit Our websites

  1. Data Collected Automatically

    When you visit our websites to read pages or download information, Tier 1 technology is used. We automatically collect and store the following non-personally identifying information:

    • The Internet protocol (IP) address from which you access our website. An IP address is a unique number that is automatically assigned to the computer you are using whenever you are surfing the web
    • The type of browser, such as Safari, Internet Explorer, or Firefox and operating system, such as Windows 7, Windows Vista, Windows XP, or OSX and Linux, used to access our site.
    • The date and time our website is accessed, for the purpose of monitoring demand.
    • The pages visited, for the purpose of improving the usefulness of our website by providing helpful links and removing pages that are not read.
    • The last website you visit, if that website contains a link to a Census Bureau web page, indicates how you found this website.

    The information we retain does not include personally identifying information. The above information is maintained in our system logs for analytical purposes. The logs may be kept indefinitely and used at any time and in any way necessary to prevent a security breach and to ensure the integrity of the data on our servers.

  2. American FactFinder

    When you make use of American FactFinder, Tier 1 technology is used. Transient cookies are used to keep track of user selections so that new requests for specific data or maps can be created more efficiently. No personally identifiable information is permanently retained on either the users or the Census Bureau's computers. These transient cookies go away completely when you exit the browser. When ordering products, transient cookies are enabled to track your order through the process.

  3. Electronic Census Bureau Surveys

    When responding to surveys over the Internet that collect personally identifiable information, Tier 2 technology is used. Use of this technology is automatic unless you decline or opt-out.

    The following also applies to personally identifiable information provided in response to a Census Bureau survey or census.

    • In response to a survey or census via the Internet, you may have to provide us personally identifiable information. For each survey and census, we provide an explanation to respondents about the confidentiality of the data and the laws that protect the data (e.g., Title 13, United States Code Section 9 (a)).
    • All web data submissions are encrypted to further strengthen the protection of the information we collect online.
  4. Blocking Web Measurements and Customization Technologies (Opt Out)

    The technologies we describe in this policy are the default settings. However, you can remove or block the use of web measurement and customization technologies by changing the setting of your browser to block cookies as described at

    Should you choose to remove or block the use of web measurement and customization technologies (opt out), we will make provide you with alternatives for acquiring comparable information or services.

Source: U.S. Census Bureau | Privacy Office | Last Revised: September 27, 2012