"Health Costs and History"

From the WSJ:

Medicare has a similar record. In 1965, Congressional budgeters said that it would cost $12 billion in 1990. Its actual cost that year was $90 billion. Whoops. The hospitalization program alone was supposed to cost $9 billion but wound up costing $67 billion. These aren't small forecasting errors. The rate of increase in Medicare spending has outpaced overall inflation in nearly every year (up 9.8% in 2009), so a program that began at $4 billion now costs $428 billion.

The Medicare program for renal disease was originally estimated in 1973 to cover 11,000 participants. Today it covers 395,000, at a cost of $22 billion. The 1988 Medicare home-care benefit was supposed to cost $4 billion by 1993, but the actual cost was $10 billion, because many more people participated than expected. This is nearly always the case with government programs because their entitlement nature—accepting everyone who meets the age or income limits—means there's no fixed annual budget. . . . .