The commercial paper (CP) market is essentially a private debt market used by corporations as a generally cheaper means of funding typical recurring operations compared to drawing on a line of bank credit. Commercial paper, as financial instrument, is by no means a recent innovation. In fact, you can read about how the CP market was affected by the many historic financial shocks experienced by the U.S. (see Panic on Wall Street: A History of America's Financial Disasters).
Although the Federal Reserve was able to artificially bring CP rates down significantly since the shocking 615-basis-point spread blowout (A2/P2 spread) of late 2008, it has not been successful in preventing an overall contraction in the CP market. The Federal Reserve calculates and published the total amount of CP outstanding every week, and as of late March commercial paper continues to slump on a monthly basis. That's while still rising 7.59% on a year-over-year basis to $1002.20 billion, a level that is still substantially lower than even the worst periods of the last two recessions.