Please interpret this graph---Why did Healthcare Costs START to rise dramatically in 1985? Anyone know WHY?

This graph (the gold line specifically) shows the Consumer Price Index for ALL items in the market basket the govt. uses to measure changes in prices/price level in the US.  The darker line shows the change in the price of medical care only.  There is a direct relationship between the two up to 1985 then there is a rapid separation.  Why was this year a watershed moment in the cost of healthcare.  I was "only" 25 at time.  I know an aging population is a part of it, but it cannot explain all the price change.  Any ideas??

Source: Economix