http://money.cnn.com/galleries/2007/fortune/0702/gallery.richestamericans.fortune/5.html has been crawled 40 times going all the way back to February 23, 2007.

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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Note

This calendar view maps the number of times http://money.cnn.com/galleries/2007/fortune/0702/gallery.richestamericans.fortune/5.html was crawled by the Wayback Machine, not how many times the site was actually updated. More info in the FAQ.