Halo 5 has sold over 5 million units worldwide which takes total franchise sales to over 70 million units. pic.twitter.com/fzL3d0X5Fe
— Daniel Ahmad (@ZhugeEX) June 9, 2016
Straight from Stinkles, Frank Connor: http://www.neogaf.com/forum/showthread.php?p=206247449#post206247449
Update: Straight from Frank Connor (343i)