Dozens of internet research firms such as Forrester Research and International Data Corp. issue projections and studies about the future of e-commerce and the internet market in general. The figures usually vary wildly. For instance, when forecasts were made for the number of internet users worldwide during 2000, predictions ranged from a low of 157 million (Morgan Stanley) to a high of 327 million users (internet Industry Almanac). What explains this huge data disparity?