From, the site say some kids starting at the age of 2 are into games and consider themselves as gamers.

The kids have spoken, and they say they belong to the group of "Gamers." Children as young as 2 years old in the United States have been found to consider themselves as gamers, with 9.7 million of them, out of the total 55.7 million gamers all over the country, being in the 2-5 age bracket. That's a lot of tiny gaming tots.

In the meantime, NPD Group's report also indicated that teens aged 12-14 spend an average of 10.6 hours a week playing their games, while those in the 15-17 bracket reflect a decline in the number of hours used up gaming.Anita Frazier, industry analyst from NPD, reads up on this patter: "The decline in teen usage of video games is likey due to diversifying, maturing interests, which translates into stiffer competition for their mind and wallet share. In addition to competition from other areas of the entertainment space, more school work, activities, and parent-imposed time limits on gaming are factors which the data suggests may be contributing to this dip in older teen engagement.

It's also probably because that's the time the teens start developing their own real social lives. The success of that, however, is a different story altogether, and was not covered by the study.

More numbers and figures in the source linked below.
heres the link

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