There's a constant stream of folks commenting on the site wishing that viewers outside the adult demo groups mattered to broadcast primetime networks (and advertisers). We're constantly repeating the same refrain that younger viewers are harder to reach in TV advertising, so they're more expensive to reach, so the shows reaching them have more expensive advertising and are therefore more valuable.
Not that this is going to convince anyone who doesn't really want to be convinced (which is plenty of people!), but just how much harder are young people to reach with TV advertising?
This is data on the average ratings from last week (10/12-18/2009) for broadcast prime time networks (ABC, NBC, CBS, Fox, CW). I'm not certifying that all weeks fall into these ranges, but the variation is likely not huge.
% of the US age group watching TV during primetime, and their estimated group population:
Adults 18-34: 31.9% of an estimated 68.99 million
Adults 18-49: 35.8% of an estimated 132.71 million
Adults 55+: 52.5% of an estimated 73.68 million
Adults 18-34 are hard to reach. And therefore advertising that reaches them is expensive.
Adults 55+ are easy to reach. And therefore advertising that reaches them is cheap.