[parsifal]

If so, that would be 1/6 of total health care costs.

parsy, who wonders if here is a link,

[Pan_Yan]

Medicare spending is growing steadily in both absolute terms and as a percentage of the federal budget. Total Medicare spending reached $440 billion for fiscal year 2007, or 16% of all federal spending. The only larger categories of federal spending are Social Security and defense. Given the current pattern of spending growth, maintaining Medicare's financing over the long-term may well require significant changes.

Wikipedia, where information is plentiful but dubious.