Call of Duty is the biggest video game franchise on the planet, with the series racking up record-breaking sales every year. But how much do people actually invest into the game? Here's a clue: it's a lot.

According to Activision, the average Call of Duty user invests 170 hours into the game every year.

That's the same amount of time as it would take you to complete Homefront's single-player campaign 42.5 times.

How does Call of Duty get people so invested? According to Chacko Sonny, head of Beachhead Studios, it's because Call of Duty has become part of our lifestyle: "there are so many things that you can do in this game," he said in an interview with VideoGamer.com. "Not only from a minute-to-minute or second-to-second gameplay experience, but also in terms of enabling you to compete and connect with people within the construct of Call of Duty already. There's so much there, and people see that potential, and it becomes like a lifestyle - it becomes something that they do, very much like being a cyclist or a musician or something like that."

"It's not just about the literal game, it's about the social experience itself," added Jamie Berger, Activision's vice president of digital for Call of Duty.

The whopping statistic was revealed as part of Activision's announcement for Call of Duty: Elite, the upcoming subscription service for the franchise that has optional premium subscriptions. VideoGamer.com went hands-on with the service last week.

Activision also announced that over 30 million people have played multiplayer Call of Duty in the past year, with 20 million of those playing every month, and 7 million users putting doing time at least once a week.

Berger thinks the upcoming Call of Duty: Elite will encourage players to invest up to double the amount of time into the franchise. "We're hearing from a lot of our players, and our research, that [Elite] would actually make them want to play more. A lot of guys now say, 'well I could find a group of people to play with, and I can join a clan, and now I can compete every day for some different thing - I'll actually double my play time versus now, because there's now more of a meta aspect to it and more of a social aspect to it.'"

Does that mean people will now be spending 340 hours a year on Call of Duty?

VideoGamer.com saw Modern Warfare 3 in action last week and has detailed the Manhattan level and the London underground tube chase.

Call of Duty: Elite will hit beta in the summer with Black Ops support, and will go live with MW3. Call of Duty: Modern Warfare 3 will be released for 360, PS3, and PC on November 8.

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