The broadcast networks didn’t enjoy Labor Day

In a week with little original programming and customary low viewership because of the Labor Day weekend, NBC sunk to a record low viewership for its prime-time programming last week, averaging 4.17 million viewers per hour, according to figures released Wednesday by Nielsen Media Research.

NBC wasn’t alone in setting records. Fox had a record low rating among viewers ages 18-49. NBC also set a record low among the group, while ABC tied its record low.

Another factor in the record lows was preemptions by more than 10% of the ABC and NBC affiliates Thursday for local programming. About 6% of CBS’ affiliates preempted its programming from 9 to 11 p.m. Sunday to carry “The Jerry Lewis MDA Labor Day Telethon.” The full list of ratings will appear in Friday’s Calendar.