The darker shaded area indicates the recent recession.
The recession seems to have caused both the healthcare inflation rate and the US Core inflation rate to just about converge. Which would have been nice, slowing down the growth of health care prices to a rate below or at inflation. Except for the recession part.
Because when people are losing their jobs and losing their healthcare coverage, people tend to be unable to afford going to the doctor--and attempt to do without medical services they need. That's not good.