People wait in line to play 'Call of Duty, Infinite Warfare' at the Paris Games Week show last October.

U.S. physical game sales of "Call of Duty: Infinite Warfare" declined nearly 50 percent in the month of November compared with last year's "Call of Duty: Black Ops III," according to NPD sell-through data sourced by two Wall Street analysts.

Activision Blizzard shares are down about 20 percent from mid-October highs and worries over poor launch sales from this year's "Call of Duty" game may be the reason why.