Interesting trends to keep an eye ahead of the NFL's Super Bowl 57 - don't sleep on the underdogs

According to a survey released by the American Gaming Association, 50.4 million Americans (around 20% of the population) will bet a total of $16 billion in the lead-up to kick-off on Sunday.

With the rest of the world watching along, we take a look at which trends and numbers can be used to help better navigate Sunday's Betting Bowl.

Bettors must be careful when looking at historical trends with so many variables involved. Instead of following blindly, savvy punters will use trends and other statistics to paint a clearer all-around picture in their quest for value.

Nevertheless, historical trends represent the most accessible and popular method of selecting bets ahead of Sunday's winner-takes-all match-up between the Kansas City Chiefs and Philadelphia Eagles.

After the conclusion of the Championship round, the Chiefs opened Super Bowl betting as 2-point favourites but heavy interest on the Eagles meant Nick Sirianni's side assumed the role with the line seeming to settle on Philadelphia -1.5.

Interestingly, the line has moved 1.5 points or more from opening to closing 18 times in Super Bowl history, with the team the line is moving towards winning 16 of those match-ups.

With so much global attention on the game each year, perhaps punters are faster to react to injury news and incorrect lines than usual.

After closing as one-point favourites against the Cincinnati Bengals, the Chiefs go into their third Super Bowl in four years as postseason underdogs for the first time in the Patrick Mahomes era.

Mahomes, who leads the betting over Eagles quarterback Jalen Hurts for Sunday's MVP award, is 7-1-1 against the spread as an underdog, the best record ATS by any QB with at least eight starts as an underdog. The only loss ATS came the last time the Chiefs entered a match when they weren't favoured in the betting - Week 6 against the Buffalo Bills.

While this year's Chiefs have the most ATS losses of any team to make the Super Bowl, the Eagles, having lost just once with Jalen Hurts under centre this campaign, are 9-3 ATS when favoured by 8 points or less.

Ranking number two in total offence and number three in total defence, the Eagles are 11-9 on the over/under in games this year, while the Chiefs are 12-8.

This year's points total is currently sitting at 49.5 points. Over the last 20 years, Super Bowl totals of 48 points or more have finished 2-9 on the over/under.

With the extra build-up and fanfare surrounding the NFL's pinnacle game, it makes sense that offence may be affected by additional nerves and adrenaline, at least during the opening moments and drives.

Additionally, the NFL has seen its last seven games (since Sunday of Wildcard Weekend) finish under the points spread, while each of the last four Super Bowls have also finished under the total.

The team that has opened the scoring has gone on to win in 37 of 56 Super Bowls (66%), including on eight of the previous 11 occasions.

With nerves potentially affecting offence early in these affairs, it could be that the team scoring first settles into the game quicker than the opposition and is able to gain better control of their emotions.

The winner of nine of the last ten Super Bowls has not trailed at the end of the first quarter or half, adding more credence to the argument that the team who goes ahead early is better able to gain control of the emotions of the day and come up with the win.

It's no secret that the betting public generally prefers the yes or over bet and this often results in value being available on the no/underside of a line. Smart punters will utilise historical no/under trends that suit Sunday's match-up and make the most of the public's biases to find an edge.

To that point, the previous eight Super Bowls have seen no safety score and there has been no successful two-point conversion in the last five editions of America's biggest sporting event.