Even if you are NOT a bettor, you will enjoy this...read to the end, you'll be glad you did.
As we prepare for the 2025 NFL season, I’ve heard a few people comment that “so many favorites covered in 2024”. I’m always up for a regression discussion so I decided to dive in to see if we should expect that in 2025.
All of this data is from Sportsoddshistory.com (excellent site for archived season win totals and as it turns out, a great site for what we needed for this article). The site has ATS win percentages for NFL favorites going back to 1952! I’m tempted to throw out the Era where players wore leather helmets and fans wore leather jackets (while punching juke boxes to make their favorite song come on). The 50’s were prime time for underdogs but let’s leave them in the dataset because 1957 was a whopper for favorites.
There are two ways I attacked this (1) looking for years where favorites were 1 standard deviation above historical average and seeing what happened the following season AND since 2023 wasn’t too shabby for NFL favorites (2) look at the best 2 year stretches for favorites and see what came next.
Let’s take the first one first…
As you probably know, Standard Deviation measures each number's deviation from the average in a data set. So take all of the numbers, find the average, then measure the average deviation of each number from the overall average (for the Math inclined, you know you actually square the averages then take the square root of the total - this gives a slightly higher weight to the numbers that are furthest from the average). *So Standard Deviation will always be slightly higher than Average Deviation if you use those in Excel.
73 data points going back to the 1952 NFL Season, over those 73 seasons NFL favorites averaged a win percentage of 47.90% with a STD DEV of 4.13. So our focus will be on seasons where favorites finished above 52.03% (47.90 +4.13).
Here are all seasons with NFL Favorites over 52.03%…
1972 - 52.3% then 1973 - 55.1% (can we put a pin in this!!!)
2023 - 52.7% then 2024 - 54.1% (can we put a pin in this as well!!!)
1990 - 52.8% then 1991 - 51.2%
1998 - 53.5% then 1999 - 46.8%
1959 - 53.6 then 1960 - 46.2%
2017 - 53.9% then 2018 46.4%
2024 - 54.1% then now?
1973 - 55.1% then 1974 42.0%
1985 - 55.8% then 1986 46.3%
1968 - 56.5% then 1969 44.1%
2005 - 58.9% then 2006 43.8%
1 STD DEV was a starting point I picked but clearly much cleaner if we look over 53% for favorites, that has only happened 8 times in 73 seasons and the following year was strongly in favor of betting underdogs.
However, if I want to play devil’s advocate, I would point out that of the seasons where favorites covered 52 point something percent of the time they hit over 50% again the next year. The only other 52 was 2007 (exactly 52% and 2008 was 49.2%. And the 3 of the top 4 data points to support this are years when I turned 1 year old, the Mets won the World Series and we faked a Moon Landing.
If I had to bet one way or the other I’m betting favorites to hit under 50% next season but the numbers are kind of a house of cards so let’s look at back to back seasons to see if we can be more confident.
So in this moment we’re coming off...
2023/2024 - 52.7% / 54.1%
And we put a pin in 72/73 (which we will now get to) here are the best 2 year runs for favorites…(all times where they went over 50% back to back) listed chronologically…
1963/1964 - Don’t want to bring up Dealey Plaza or the fact that Oswald was eating lunch at the time of the shooting, so let’s go with Valentina Tereshkova, a cosmonaut who became the first woman in space.
‘63 50.3% / ‘64 50.3 %
1965 - 46.8%
1967/1968 - Don’t want to bring up RFK or MLK so let’s go with the first successful human heart transplant (thank you South Africa)
‘67 50.0% / ‘68 56.5%
1969 - 44.1%
1971/1972 - Don’t want to bring up Vietnam War protests so let’s go with Disney World Opening.
‘71 50.6% / ‘72 52.3%
1973 - 55.1%
1972/1973 - Don’t want to bring up the Watergate scandal so let’s go with me being born.
‘72 52.3% / ‘73 55.1%
1974 - 42.0%
1975/1976 - Don’t want to open the wound of the SS Edmund Fitzgerald sinking in Lake Superior so let’s go with the founding of Microsoft.
‘75 51.4% / ‘76 50.5%
1977 - 45.2%
1990/1991 - Don’t want to bring up the first Women’s World Cup of Soccer so let’s go with the Persian Gulf War.
‘90 52.8% / ‘91 51.2%
1992 - 49.3%
2016/2017 - Don’t want to bring up Trump/Hillary (or the fact that I’m running out of material) so let’s go with the Brexit vote that had the UK leave the EU.
‘16 50.0% ‘17 53.9%
2018 - 46.4%
This looks pretty good. I feel like we have some equal and opposite forces in play. The early 70’s saw a three year run of favorites but even ‘71 & ‘72 were both lower win % than both of the past 2 seasons. I think this gives me confidence we are likely to see 2025 regress to underdogs hitting at over 50% rate. I’ll be keeping track and if we see a 10-5 run for favorites adjusting contest picks the following week accordingly.
