Every month we publish a snapshot of the stock market performances of more than 130 companies that earn revenue from customers in the payment card industry. This issue features the four publicly traded card payment networks and the 20 publicly traded issuers of payment cards. Combined, the card networks held a market capitalization of more than $1.333 trillion as of December 31, 2024, up from $1.089 trillion one year before. The largest growth was at Discover. Its market cap was up 54.82%, fueled by its pending acquisition by Capital One Financial. The 20 publicly traded issuers of payme...