NFL Betting 2010: Key Numbers

Added on Jan 04, 2011 by Jack Thurman in

NFL

If you’ve read my NFL handicapping articles over the past season you’ve no doubt seen a number of references to ‘key numbers’. This is a very important concept in football betting, and especially NFL betting. The premise is simple–since certain margins are victory are more common in the NFL it means that certain pointspreads are more significant as a result. The pointspreads that correlate to the most common margins of victory are called ‘key numbers’.

The most common application of his concept is on the number 3. The three point margin, year in and year out, is the most commonly occurring margin of victory in the NFL. As a result, a move from -1′ to -2′ is of less statistical significance than a move from -3 to -3′. A move from -2′ to -3 is called a ‘move on to a key number’ while a move from -3 to -3′ is called a ‘move off a key number’. Bookmakers are in general more hesitant to move onto and off of a key number not only due to the intrinsic importance of the number but because of the resulting impact on public perception–on balance a line set at a key number will divide action more evenly than one that is not.

In addition to the number 3 the other significant key number is 7. In most years over 25% of all NFL games will be decided by either 3 or 7 points. Of secondary importance are multiples of these key numbers like 6, 10, 14, etc.

With the 2010 NFL regular season in the books, we can look at the breakdown of victory margins for the season. 47 games were decided by 3 points which equals 18.7%. The significance of the 3 point number (and its corresponding pointspread) can be underscored by the big drop down to the *second* most frequently occurring margin of victory: 18 games were decided by exactly 7 points (7%). As we noted above, in a given year over 25% of all NFL games will be decided by either 3 or 7 points and 2010 saw 25.7% of all games decided by one of these two margins.

So pay attention to those key numbers–not only has it been of paramount importance in my handicapping experience the raw data clearly illustrates the value of the concept.