Betting NFL Teams That Move from -3 to -2.5

There is a big game this week. You have conducted your typical research but cannot find any advantage to separate the two teams. The home team is given the standard -3 spread in the opening line, but this one is too close to call and you decide not to risk it.

But wait! The day before kickoff, the line moves to -2.5. Reasoning that this is a far more beatable line, you say what the heck, and decide to throw down a unit or two.

What is wrong with this picture?

Some may argue that nothing is wrong, claiming this is a perfectly logical approach to spread betting. After all, over the past 4 NFL seasons 14.2% of games have ended with 3-point margins while only 8.4% of games finish closer than 3 points (including ties).

Based on this, it makes sense to pounce on a line when it shifts from -3 to -2.5, right?

Wrong!

There is no evidence that suggests a line moving from -3 to -2.5 increases the team’s chances of covering.

If you already knew this, pat yourself on the back for being an educated bettor. If you did not, prepare to be awakened.

Comparing Favorites at -3 to -2.5

This chart shows the ATS records of favorites since 2012 when the line is -3.

Year	Record ATS	ATS Win %
2018	10-7-1	58.8%
2017	16-20-7	44.4%
2016	15-17-3	46.9%
2015	19-17-4	52.8%
2014	13-18	41.9%
2013	14-13-6	51.9%
2012	13-22-1	37.1%
Total	100-114-22	46.7%

Not very good. 3-point favorites are in a slump as of late. If getting that extra half-point really helps, we should expect improvement across the board for our 2.5-points favorites, right? Take a look.

Year	Record ATS	ATS Win %
2018	4-5	44.4%
2017	12-7	63.2%
2016	14-11	56%
2015	6-11	35.3%
2014	12-5	70.6%
2013	9-13	40.9%
2012	8-13	38.1%
Total	65-65	50%

I probably have some readers screaming at me through the screen right now saying: See! I told you! 2.5-point favorites are better!

Hold your horses, folks. This 3.3% increase in ATS winning percentage only matters if we can find correlation. In other words, we need to find numbers that prove a 2.5-point favorite is more likely to win than a 3-point favorite every time.

According to the 2 tables above, this correlation does not exist. For example, look at what has been going on so far in this NFL season.

3-point favorites are winning ATS at an awesome clip, 58.8% of the time. We would expect 2.5-point faves to perform even better, but they do not. This year, 2.5-point favorites are winning a dismal 44.4% of the time ATS.

Think this is just one occurence? An outlier? Think again.

We see the same story in 2015 and then again in 2013. 2.5-point favorites sometimes win more often than their 3-point counterparts. This does not help us construct a winning approach.

Remember, if you did not like a team’s chances at -3, a line shift to -2.5 does nothing for those chances!

A half-point on the spread is not enough to turn a team from a poor bet to a must-bet. Do not fall for this trap!