What happened to the Saturday morning cartoon?

In a time not so long ago, Saturday mornings were indicative of one and only one pastime for children — watching cartoons. Throughout the '70s and '80s, the broadcast networks ABC, CBS and NBC dominated the Saturday morning airwaves by inundating children with cartoons. Cartoons on these networks used to earn ratings of more than 20 million viewers. Today, network Saturday morning cartoons only exist on ABC Kids, FOX Kids and Kids’ WB!, the latter two networks either did not exist or did not air cartoons two decades ago. Current successful cartoons on FOX Kids or Kids’ WB! can garner a mere two million viewers. That statistic does not even take into consideration that the population of children in the U.S. has increased by approximately ten percent over the last 20 years. Due to this precipice in viewers, network cartoons are left struggling to make money while advertisers remain befuddled without a mainstream channel to promote new toys and products to children. Why have children stopped tuning in on Saturday mornings to network cartoons and what are the ramifications of this change?