I am interested in understanding how Physics research is funded and which particular sub-fields as well as categories (.e. theoretical vis a vis experimental/observational) are preferentially funded today as well as historically (e.g. during WWII and the Cold War era, particle physics was particularly well-funded--but there's been a shift towards the biological sciences in the past decade). Also, how does this compare to other natural sciences? I understand that the NIH and the US Dept of Defense as well as foundation grant money are all actors in these funding schemes but where could I find more specific data?