Wagering against the spread (ATS) on NFL games often leads to tough decisions and requires you to research all the intangibles. My weekly “Golden Rules” examines historical ATS betting trends relevant to specific games. Consider these Golden Rules to be the tie-breakers, the game-changers and the intangible factors you are looking for.
HOW DO FAVORITES PERFORM IN THE SUPER BOWL WHEN THE SPREAD IS OVER A FIELD GOAL BUT NOT GREATER THAN A TOUCHDOWN?
Dating back to the 1978 season (or the January 1979 Super Bowl), the average spread on Super Sunday is 7 points. Has there ever been a more football number than 7? Or a luckier number? For as common as seven points is in the NFL, only three of the 49 Super Bowls have ever been decided by a converted touchdown. In fact, only 18 of the 49 Super Bowls (or 37%) have even seen margins of victory fewer than seven points. This year, Carolina is favored over the Denver Broncos by 5.5 points – the first time since Super Bowl XXIII in January 1989 in which the line fell in between 4.5 and 6.5 points.
From the 1993 season through to 1997, the Super Bowl’s average point spread skyrocketed to 13.6 – an average of two touchdowns. But the big games this decade are far from your father’s Super Bowls of 20 years ago. The average point spread in the Super Bowl over the past five seasons has dipped below a field goal. But spreads between 3.5-7.0 are not uncommon. In the five Super Bowls before that, four of the contests saw a line greater than three and less than or equal to seven.
Before I can look specifically at 3.5-7.0-point spreads, I wanted to understand how favorites generally perform in the big game. The chart below divides up the past 36 Super Bowls into six-year increments and summarizes the ATS winning percentage of the favorites. The straight-up results for favorites are also included for a frame of reference.
Throughout my analysis below, I have excluded pushes from the determination of a team’s ATS winning percentage or, in other words, a win only reflects profitable outcomes. As well, the year refers to the season, not the year in which the Super Bowl took place.
We all remember that 12-year period of Super Bowls – let’s call it the dark ages? It started with a Los Angeles Raiders rout of an explosive Washington team following the 1983 season and ended with Steve Young ripping the monkey off his back in the mid-90’s versus the San Diego Chargers. Over half of these matchups were decided by three touchdowns and the average margin of victory over all 12 was 23 points. Those dark ages are mostly represented by the second and third bars from the left. Since then, the ATS results have plummeted and the straight-up success of favorites has declined to new lows over the most recent six-year period.
Since 1978, favorites are 23-14 straight-up in Super Bowls, but only 16-19-2 against the spread. The ATS performance over the past 20 years drives the results down further as favorites have only covered 25% (5 of 20) of the past twenty Super Bowl matchups.
Next, I wanted to understand how close favorites were coming to covering. The following chart analyzes just that. The pink bar indicates by how many points the favorites outscored their opponents. The black dot represents by how many points the favorites covered (or failed to cover).
In this chart, pink bars above the “zero line” signal favorites who won outright. They covered the spread if the black dot is above the line too. The distance between the bar and the dot reflects the size of the point spread. For example, the Patriots were 12.5 point favorites versus the Giants following the 2007 season and the Seahawks were mere 1-point favorites over the Patriots last year.
This chart shows how underdogs have been the teams blowing the spread wide open over the past 12 Super Bowls. Based on this historical trend, there is very little upside to gain by taking the favorite as the spread-adjusted margin never exceeded ten points during this period. On the underdog side of the chart, there are almost as many lopsided upsets than there were narrow victories by underrated squads.
Now that I have identified the general historical trends of favorites, I decided to delve deeper into the impact of a Super Bowl spread between 3.5-7.0. The following chart splits up the Super Bowl ATS results since the 1978 season by the size of the line.
Teams entering Super Sunday as greater than touchdown favorites have tasted plenty of ATS success; however, those favored by seven or less have not. Since the 1978 season, Super Bowl favorites are 9-15-1 when the spread is under 7.5. Favorites are more successful against the spread when the line is lowered to a field goal or less, but the results are still at a .400 ATS winning percentage.
So far, all indicators are pointing towards the underdog AFC champions. But it’s time to look away from general Super Bowl trends and focus instead on this season’s final two combatants. How have Denver and Carolina performed in similar tight matchups when the spread is between 3.5-7.0? The next chart explores this question and a couple of other situations from the Super Bowl. For this analysis, I focused solely on the past three seasons since Cam Newton first started to see success with the Panthers.
Under the first comparison, the Broncos hold a slight edge over the Panthers when the spread for all regular season and playoff games have been between 3.5-7.0. The other two comparisons are not as related to what has been discussed above and the two Super Sunday opponents have split the difference.
Both teams take to the road for the Super Bowl and Denver maintains a strong ATS winning percentage (.583) on the road compared to the Panthers (.480). However, since Cam Newton first led Carolina to the postseason, the Panthers have exceeded oddsmaker expectations in the playoffs in comparison to the Broncos. The Panthers have a 3-2 ATS record in the playoffs over the past three seasons; whereas the Broncos have a 2-3-1 mark over the same period. If I had assumed pushes were equal to half a win, the gap between the Panthers and Broncos would have tightened considering the smaller sample size of playoff games.
Notwithstanding the far right analysis in the final bar chart, every trend leans toward the underdog Broncos. The Super Bowl has become far more underdog friendly than it ever has been. And that’s especially true if the spread is caught between a field goal and a touchdown.
Golden Rules say to take Denver
Bob Sullivan writes periodically for SportingCharts.com and can be followed on Twitter at @mrbobsullivan.
The Golden Rules are 2-7-1 during the 2016 playoffs
You can access the previous Weekly Golden Rules Analysis below.
The data on NFL regular season spreads was accessed directly from scoresandodds.com or via Sunshine Forecast whose current source is scoresandodds.com. Spreads are collected as close as practicable to game time.