The Entertainment Software Association's annual "Essential Facts" briefing on the state of the US video game market is considered one of the most reliable and comprehensive looks at who is actually playing games in this country. And for years, that survey has been showing video games consistently growing away from their outdated, "just for kids" image.

The 2011 report (PDF), for instance, showed the average US gamer was 37 years old, with only 18 percent of gamers coming in at under 18. That's a distinct change from the 2005 report [PDF], which showed an average gamer age of 30 and counted a full 35 percent of gamers as minors. The changing numbers gave the distinct impression that the game industry was succeeding in broadening its audience across all age demographics, and holding on to dedicated consumers that grew up with video games as they continued to age.

So it was a bit shocking to notice (as Twitter user Superannuation did recently) that the ESA's 2012 report (PDF) essentially eliminates seven years worth of market-broadening progress for the industry. The gaming demographics of 2012 look incredibly similar to those of 2005, with an average gaming age of 30, and a full 32 percent of the gaming public being made up of minors.

What happened to that much broader gaming market reported in 2011? Did a lot of older folks suddenly stop playing games in the last year? Did a bunch of kids finally convince their parents to buy them the Wii they've been asking for since 2006? Actually, the seemingly abrupt change in the numbers is the result of a change in methodology that makes the 2012 numbers much more reflective of reality than those that came in recent years.

Getting data that's "more fully reflective"

Up through 2011, the ESA screened out the non-gamers from its annual questionnaire by asking each respondent, "Do you have a video game console in your home or do you have a PC that's used primarily to run video games." In 2012, that screening question was expanded to also include play on "a dedicated handheld system (like a PSP, etc.), a wireless device/tablet (e.g., iPad) or a phone used to play games." Anyone that played games across any of those devices for at least an hour a week was considered a "gamer" for the survey, while those that played at least ten hours were labeled "serious" gamers (even if they were just playing Words With Friends for those ten hours).

The expanded universe of "gamers" captured by the newly worded question creates "survey data that is more fully reflective of everyone who is playing games at this point," ESA Vice President Dan Hewitt told Ars Technica. It's also data that paints a very different picture of the overall game market than the one we thought we knew in recent years.

The average person actually buying games in the US, for instance, is a 35-year-old in 2012, not the 41-year-old described under 2011's outdated wording. The expanded gaming universe is also a little closer to gender parity; only 53 percent male in 2012, compared to the 58 percent reported in 2011 (2005's audience was reportedly 55 percent male). In fact, women aged 30 and older now represent a significantly larger portion of the total population of US gamers than boys 17 and younger (no word on how that comparison shakes out when spending or average hours played are taken into account, though).

Though the impact of phone and tablet games was being felt in the industry well before 2012, Hewitt says the new wording doesn't invalidate the surveys that came in recent years. "I think [the old surveys are] an accurate assessment of what we said they were an assessment of, and it's important not to overstate what was previously being surveyed," he said. "The information before is still true and is still valid."

More than anything, though, the abrupt change in the data shows that the supposed broadening of the US game market has been a somewhat illusory phenomenon. Rather than the persistent demographic shift we thought we were seeing over the last seven years, what we've actually been monitoring was more of a generational platform shift, where the traditional PC and console game market continues to age while younger players gravitate towards smartphones, tablets and portable systems. Call it the Angry Birds effect.

And you can only ignore that effect for so long before your data reaches a breaking point, as Hewitt acknowledged. "At some point you can kind of see a situation when the market changes and the way people play games change," he said. "At some point you're going to have to change your survey instrument and have a year like we have now… to ensure that your survey and the statistics that stem from that survey maintain their relevance, so that's what we're doing right now."

Wise words for anyone who still thinks they can safely ignore the effects that mobile and portable gaming are having on the market.

Listing image by ESA