Maybe that approx 20% drop in abortions has something to do with the halving of the unemployment rate in the same period? I would say that the rate of abortions will drop even further if the rise in the standard of living in the U.S. can continue. You had better hope that Trump doesn't derail it.
Maybe the drop in the incidence of abortions would drop even further if everyone in the U.S. had free access to healthcare - none of this mucking around with insurance companies etc.