"[T]he huge jump in prescription drug spending that occurred in 2014 was unforeseen. In 2013, spending on prescription drugs grew by only 2.4 percent, but in 2014, it skyrocketed to 12.2 percent. Some of this increase in spending on prescription drugs is due to expanded coverage, and some is due to the acceleration in prescription drug prices. A major source of this growth was the introduction of Sovaldi in December 2013, and Harvoni in October 2014.... U.S. sales of hepatitis C drugs seem to have stabilized at about $14 billion per year, which equates to about 150,000 persons treated per year (at a rate of $90,000 per person treated)."