Broadcast networks produced a 3.5% increase in the number of combined commercial minutes in prime time last year -- a sign that networks may be forced to squeeze in more spots to keep revenues growing. Nielsen figures show that the total rose to 5,688 minutes in 2008, topping the total of 5,492 the year before.
While prime time saw a notable boost, daytime commercial minutes were about flat, with a total of 3,811 increasing less than 1% over 2007. Daytime covers 10 a.m. to 4:30 p.m.
Here's a chart from from the latest Nielsen Television Audience Report with the data.
Click for a full sized image.