Datahound's first post...
Most of the data readily available from NIH RePORTER are on a 'per grant' basis. However, these data may be more revealing when they examined on a 'per investigator' basis. To obtain such data, the results for all R mechanism grant awards were downloaded from NIH RePORTER and aggregated the data for each unique investigator.
Disclaimer: While I have done my best to perform this analysis fairly and accurately, there are a small number of records for which the interpretation is problematic. These represent small amount of funding although their inclusion/exclusion could influence the inferred number of investigators to a small degree. Only the contact PI was included for multiple PI awards.
R mechanisms from R01 through R56 were included with the exception of R13 awards (conference grants) and RC1 and RC2 awards made for FY09 and FY10 as part of the American Recovery and Reinvestment Act (ARRA). Approximately 75% of the awards examined were R01s, 10% R21s, 5% SBIR/STTR (small business) awards, and 10% other mechanisms. Note that the number of awards includes all award types including new, competing continuation, non-competing, and supplements rather than unique grant numbers.
The number of awards and the number of investigators are shown below.
Aggregated over all 8 years, a total of 53526 investigators were funded by these mechanisms.
From these data, the number of investigators who left the R-funded investigator pool each year (that is, those who were funded one year but not funded the next year) as well as the number of investigators who joined the funded investigator pool (that is, those who were not R-funded one year but were in the subsequent year) could be determined. The dynamics of the investigator pool determined in this way is shown below:
The results of this analysis reveal the impact of ARRA and the sequester. From 2006 to 2007, the number of R-funded investigators increased by 117 as 5317 investigators funded in fiscal year 2006 were apparently no longer funded in 2007 while 5434 investigators not funded in 2006 were now funded in 2007. A drop of 228 investigators occurred from 2007 to 2008. In contrast, with the advent of ARRA, the large bolus of investigators joined the funded pool in 2009. Note that this analysis does not include RC1 ("Challenge") and RC2 ("Grand Opportunity") grants which would presumably swell these numbers further. The number of investigators held fairly steady from 2009 to 2010 but then fell dramatically after ARRA with 7059 investigators leaving the funded pool and only 4628 investigators added in 2011. The number of investigators dropped slightly again from 2011 to 2012 and then more substantially in 2013 due to the sequester with a net loss of 1001 investigators. Overall, over this period, the number of R-funded investigators dropped by approximately 6%.
Since there are a total of 53526 unique investigators and approximately 27000 investigators for each of the eight fiscal years, each investigator, on average, was funded for a total of four years during this period ((27000 X 8)/53528 = 4.03). More on the distribution of funding for these investigators soon...