R&D efficiency, measured simply in terms of the number of new drugs brought to market by the global biotechnology and pharmaceutical industries per billion US dollars of R&D spending, has declined fairly steadily. We call this trend "Eroom's Law", in contrast to the more familiar Moore's Law ("Eroom's Law" is "Moore's Law" backwards). Moore's Law is a term that was coined to describe the exponential increase in the number of transistors that can be placed at a reasonable cost onto an integrated circuit. This number doubled every 2 years from the 1970s to 2010. The term is used more generally for technologies that improve exponentially over time. The data in Fig. 1a show that the number of new US Food and Drug Administration (FDA)-approved drugs per billion US dollars of R&D spending in the drug industry has halved approximately every 9 years since 1950, in inflation-adjusted terms.
-- Jack W. Scannell, et al., "Diagnosing the decline in pharmaceutical R&D efficiency," Nature, 1 March 2012