We'd have to look at the composition of this spending. I'm betting the growth is mostly in Medicare/Medicaid, which is driven by inflation and not increases in the real volume of services. I'd fact check that, but my budget spreadsheets are a few years out of date.
[WS:] It is health care and prescription drugs indeed. Check NIPA tables 3.12 (govt social benefits), 3.16 (govt' current expenditures by function) as well as table 2.4.5.u (Personal consumption expenditure - which includes Medicare/medicaid): http://www.bea.gov/national/nipaweb/SelectTable.asp?Selected=N
>From table 2.4.5u:
Line 138 prescription drugs increased 21 times between 1980 and 2006
Line 240 health insurance increased 11 times between 1980 and 2006
Line 241 health care increased 16.6 times
For a comparison, durable good increase is 4.9 times Govt social welfare spending increase is 4 times (from table 3.16 line 39).
Wojtek