The current Sports By Date inventory for April 26, 2014 through April 19, 2015 has over three hundred individual entries, each with their own customized audience estimate.
29 hours after I posted the above, before they headed out the door at 30 Rock on Friday evening, the fine folks at NBC noted this on APT:
Posted: 04/25/2014 07:25:36 PM
Type: New Booking
Message: NFL 2014 REGULAR SEASON FOOTBALL (including FOOTBALL NIGHT IN AMERICA) is now booked on the following dates: Thursday 9/4 and 11/27; Sunday 9/7-12/28. Please note: impact to dayparts immediately preceding and immediately after each game will be posted by COB on Monday 4/28. In addition, optional and stand-by programming, advertising and promotional guidelines, and preliminary operating conditions will be posted as well. Please advise clearance.