Bill wrote about the dead zone for broadcast television. That Friday and Saturday became dead zone for the broadcast nets is not exclusively a byproduct of migration to cable. Nor is it exclusively a byproduct of fewer viewers on those nights. It’s a byproduct of the unholy (for the broadcast networks) union of both.
Below is the percentage of TV viewers 18-49, 18-34 and 50+ watching TV by night, by hour in primetime for the last week (Wednesday October 20 through Tuesday October 26). These are based on preliminary numbers, but unlike data for individual shows, the numbers aren’t subject to much revision. I didn’t have the data for 50+ on Friday/Saturday, so I didn’t include it. But this was more about the distribution of viewer availability by hour, by night rather than another excuse to write about why advertisers don’t care about the 50+ crowd nearly as much as the under 50 crowd.
The above gives you only one slice of the problem. Ideally I would have overlaid the percentage of people viewing cable (or at least something other than the broadcast nets) by hour, by night, but as a reference point on Monday from 9p-10p ABC, CBS, FOX, NBC and the CW accounted for 32% of all 18-49 viewing. Last Friday those networks accounted for 19% of all 18-49 viewing between 9pm-10pm.
Keep in mind it’s only one week of data. Averages over a longer period of time are more telling, but sadly I did not have that data. There were special circumstances like Major League Baseball playoffs that bring in some viewers who might not have otherwise been watching TV.
Some might be surprised that there were more young adults watching TV on Saturday than Friday, especially since the ratings powerhouse that is the Yankees played Friday night and Saturday night was Giants/Phillies, but Saturday also had higher profile college football in primetime (Missouri/Oklahoma on ABC and Tennesee/Alabama on ESPN).
The perspective of the relative night by night landscape is a bit different depending on whether you look at it on an absolute or relative basis. On an absolute basis, for example, there was 11.5% less 18-49 viewers available at 8pm Friday compared to 8pm Sunday. On a relative basis though, that’s a 30% decrease in 18-49 viewers on Friday at 8pm versus Sunday.
If I'm a broadcast network, I'm probably focusing on the relative percentages. Why? Because if you use the absolute numbers you say, "the difference between Friday at 8 and Monday at 8 is only 9%. CBS should be able to achieve 91% of the 18-49 rating it achieves on Monday!" If you use the relative comparison you say "CBS can't hope to achieve better than 75% of its Monday 8pm rating on Friday at 8pm." The truth is, CBS hasn't been able to achieve even that. Whether that's specifically because of the programming or that fewer viewers + cable migration is a compounded problem, a little of both or neither is open to debate.
There are those who will use some sporting or special event like the Olympics and say "see! if you program Saturday night with programming people want to watch, people will show up!" But if I'm a broadcast network I'd view such thinking as mostly nonsensical.