The National Institutes of Health (NIH), a part of the US Department of Health and Human Services and the country s medical research agency, is the world s largest funder for medical research. The NIH website states that more than 80% of the agency’s budget is used to cover research costs at over 2,500 universities and research institutions.

On its Research Portfolio Online Reporting Tools (RePORT) website, the NIH also publishes information on its expenditures. We used data on funding estimates for some diseases and medical conditions published in the RePORT website to create this visualization. A complete listing of the funding estimates for each of the 233 reported categories of disease, condition, or research area from 2009 to 2012 can be found on the Estimates of Funding for Various Research, Condition, and Disease Categories webpage. Details on how the NIH-funded projects are categorized can be found here.

Please note that the graphic has been updated to include more diseases, and a previous scaling error that resulted in some bubble sizes being disproportionately larger has been corrected.