Google : Since 1999 a 437,115 percent increase

From the Deloitte Technology Fast 500 (pdf) :

Is it enough to measure success by revenues alone? How about when your company name actually becomes a hip verb, when your site is used for everything from getting the lowdown on possible love interests to finding critical medical information? Or when your IPO becomes the cause célèbre of the business world?

Google is an Internet phenom if ever there was one. But unlike so many earlier phenoms that tanked, Google has revenues. Indeed, they posted $220,000 in revenues in 1999 and $961,874,000 in 2003, an increase over five years of 437,115 percent.
A play on the word googol, which refers to the numeral 1 followed by 100 zeros, Google is now an unlikely household name. The search engine company first opened its doors in 1998, and while in beta mode, answered 10,000 search queries a day. Word got out and in one year, the service was answering more than half a million queries daily and had Red Hat as its first commercial search customer. Oh, and they tossed the beta label, as well.