Before getting into the details, we should probably take a look at the basic concept of "key numbers" as it seems that often times even moderately experienced sports bettors don`t understand key numbers… First off, football is unique among the major sports in terms of how points are scored. In baseball, hockey, and soccer, all scores are valued as a single point. These sports also tend to have low scores and the average margin of victory is extremely low so pointspreads aren`t used in the same way as they are in football betting and basketball betting. Basketball scores come in increments of 1, 2, or 3, but the high amount of scoring makes for an even distribution of final scores. As a result, basketball is likely the easiest sport to wager on in terms of lines offered. Football betting gets more complicated because the scoring comes in "chunks" of 3 points (field goal) and 7 points (Touchdown and P.A.T.). There are also a small number of other scoring possibilities with safeties providing 2 points, missed extra points making the touchdown worth only 6, and/or the 2 point conversion making 8 a possibility as well. Scoring in football tends to take place on average only about 8 times per game, so unlike basketball; the final scores do group around certain numbers, known as "key numbers". The major key numbers are 3 and 7, but 1, 4, 6, 10, 13, 14 have a high likelihood of being the final margin of victory as well and are often referred to as minor key numbers. If we look at how all these numbers relate to 3 and 7, it`s easy to see whey they occur frequently. The following chart shows the frequency of certain final scores for the 2001 NFL season as well as the relationship of the number to a combination of Touchdowns and Field Goals:

3	17.3%	Field Goal
7	9.7%	Touchdown
10	6.9%	Touchdown + Field Goal
4	5.6%	Touchdown - Field Goal
1	4.4%	TD -Two Field Goals, or Missed Extra Point
6	4.4%	Two Field Goals
14	4.4%	Two Touchdowns
13	4%	Touchdown + 2 Field Goals