Since its launch in 2004, Call of Duty has amassed numerous new variants and widespread success worldwide. Now, new research shows that this line of games is ranked second in terms of console units sold as of January 2020. Black Ops 3 is mostly responsible for this achievement.
https://www.notebookcheck.net/The-Call-of-Duty-series-has-made-the-list-of-best-selling-Xbox-PS4-titles-with-over-60-million-units-sold.457663.0.html