100,000 separate data breaches over a two-year period have yielded a 300 percent increase in stolen credentials. 15 billion usernames and passwords for a range of internet services are currently for sale on underground forums fueling account takeovers on the internet. Credentials for accessing bank accounts and streaming services are being flogged on the dark web. Most of the credentials are from consumers, and while many are sold on forums for an average price of $15.43 many also are given away for free.
Source: https://threatpost.com/15-billion-credentials-currently-up-for-grabs-on-hacker-forums/157247/