http://phil.cdc.gov/ has been crawled 271 times going all the way back to February 29, 2000.

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 7, 2011

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January 26, 2011

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February 2, 2011

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February 3, 2011

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February 10, 2011

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February 19, 2011

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March 2, 2011

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March 3, 2011

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March 25, 2011

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Apr
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April 7, 2011

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April 9, 2011

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April 29, 2011

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April 30, 2011

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May
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May 5, 2011

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May 7, 2011

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May 11, 2011

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May 12, 2011

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May 15, 2011

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May 18, 2011

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May 25, 2011

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May 31, 2011

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Jun
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June 2, 2011

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June 8, 2011

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June 10, 2011

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June 12, 2011

1 snapshot

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June 14, 2011

1 snapshot

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June 15, 2011

1 snapshot

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June 22, 2011

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July 6, 2011

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July 7, 2011

1 snapshot

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July 21, 2011

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July 24, 2011

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July 28, 2011

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Sep
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Oct
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Nov
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Dec
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Note

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