The medical science sector has shown the largest increase in "market share," according to a recent brief from the National Science Foundation, which tracked academic R&D spending between 1973 and 1996. During that period, medical sciences' share increased from 22.4 to 27.6 percent. Each percentage point was worth $230 million in 1996, translating to $6.35 billion. At the same time, engineering, computer sciences and astronomy also gained in their share of the R&D pie. While the overall amount of money available increased, certain sectors saw a decrease in share, including social sciences, biology and physics.