We examine the current state of the U.S. public corporation and how it has evolved over the last 40 years. After falling by 50 percent since its peak in 1997, the number of public corporations is now smaller than 40 years ago. These corporations are now much larger and over the last twenty years...

From 1963 through 2015, idiosyncratic risk (IR) is high when market risk (MR) is high. We show that the positive relation between IR and MR is highly stable through time and is robust across exchanges, firm size, liquidity, and market-to-book groupings. Though stock liquidity affects the...