Football scores come in threes and sevens, so final margins pile up on a few numbers. Across 3028 regular-season and playoff games from 2015 to 2025, 14.83% were decided by exactly 3 points and 8.69% by exactly 7, against 4.52% by 1, 4.59% by 2 and 4.62% by 4. From the nflverse games file: source, read 2026-10-12.
Those are the key numbers. The next tier is far behind: 6.94% by 6, 4.76% by 10 and 5.15% by 14. From the nflverse games file: source, read 2026-10-12.
What a key number does to a spread
When the closing spread sits on a key number, the favourite often wins by exactly that number and the spread bet is a push. Of 433 games that closed with a 3-point spread, the favourite won by exactly 3 in 44 (10.16%), a push on the spread; of 172 that closed at 7, the favourite won by exactly 7 in 11 (6.40%). An underdog winning by 3 is not a push, so those games are not in the count. From the nflverse games file: source, read 2026-10-12.
So the half point either side of 3 is the most valuable half point in football: at −2.5 a three-point win covers, at −3 it is money back, at −3.5 it loses. That is why books move the price on a 3 rather than the line, and why buying off 3 costs more than buying off 5. What a push is worth shows the same effect on a total.