As private markets have grown in size, the number of public companies listed on exchanges has fallen from more than 8,000 in the 1990s to fewer than 4,000 today, explains Jason Singer of Apollo Global Management. (This is not an offer of apollo’s investment advisory services and is neither an offer to sell nor a solicitation of an offer to buy any securities. An offering is made only by a prospectus or private placement memorandum. For additional information, please see the legal page of apollo’s website)