http://www.cdc.gov/pcd/ has been crawled 234 times going all the way back to August 5, 2003.

A crawl can be a duplicate of the last one. It happens about 25% of the time across 420,000,000 websites. FAQ
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January 5, 2011

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January 26, 2011

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February 10, 2011

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Apr
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April 14, 2011

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April 19, 2011

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April 29, 2011

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May 27, 2011

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July 19, 2011

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July 21, 2011

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July 27, 2011

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Aug
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Note

This calendar view maps the number of times http://www.cdc.gov/pcd/ was crawled by the Wayback Machine, not how many times the site was actually updated. More info in the FAQ.