"The "Mass Use of Inventions" ....shows that the time required for adoption by 25 percent of the US population steadily declined over the past 130 years. For the telephone, 35 years were required compared to 31 for the radio - a reduction of 11 percent, or 0.58 percent per year in the 21 years between these two inventions. The time required to adopt an invention dropped 0.60 percent per year between the radio and television, 1.0 percent per year between television and the PC, 2.6 percent per year between the PC and the mobile phone, and 7.4 percent per year between the mobile phone and the World Wide Web. Mass adoption of the radio beginning in 1897 required 31 years, while the Web required a mere 7 years after it was introduced in 1991 - a reduction of 77 percent of 94 years, or an averfage rate of 1.6 percent reduction in adoption time per year. Extrapolating this rate for the entire twentieth century results in an overall reduction of 79 percent for the century. At the current rate of reducing adoption time of 7.4 percent each year, it would take only 20 years at today's rate of progress to achieve the same reduction of 79 percent that was achieved in the twentieth century. At this rate, the paradigm-shift rate doubles (that is, adoption times are reduced by 50 percent) in about 9 years. Over the twenty-first centure, eleven doublings of the rate will result in myltiplying the rate by 2 [to the power 11], to about 2,000 times the rate in 2000. The increase will actually be greater than this because the current rate will continue to increase as it steadily did over the twentieth century."