What does count mean?

This shows the number of times a particular keyword has appeared in our database. E.g. Our database currently holds 298,656,002 words. A count of 147 tells us that this particular word has appeared 147 times in (this is over 160 days). Our keywords are taken from major metacrawlers (a service that queries all the main search engines simultaneously). Our main sources are Metacrawler and Dogpile, the two largest Metacrawlers on the net. Metacrawlers have the major advantage of matching the search profile of the search engines very closely. But are not subject to the same kind of skew from software robots that continually check web site and pay per bid positions.