You can wager on who will win the game, on how much money will be bet on the game and also on how many people will watch the game.
The OVER/UNDER for the national American television rating for Super Bowl XLVII is 46, according to Bovada. The sportsbook is also lining an O/U on the average viewership of 111 million.
And even though the 49ers are favored on the field, Baltimore's TV market is favored to have a higher viewing rating. Bovada set -150 in the market-vs.-market match-up, with San Francisco getting +110.
For Super Bowl television ratings tutorial purposes, the Giants' victory over the Patriots a year ago set a new record for average viewership at just over 111 million. It drew a rating of 47. Two years ago, the Packers' win over the Steelers drew a 46 rating.
But before that, the most recent Super Bowl to grab a rating of at least 46 came 15 years previous, when the Cowboys beat the Steelers in Super Bowl XXX. (See the latest Super Bowl TV ratings props here).
Overall, only 11 of the first 46 Super Bowls have drawn a television rating of at least 46.
Average viewership for the Super Bowl has, for the most part, steadily increasing over the years.
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About 24 million Americans watched the Packers beat the Chiefs in Super Bowl I; five years later 56 million watched the Colts out-ugly the Cowboys in Super Bowl V; a decade after that 85 million saw the 49ers top the Bengals in Super Bowl XVI; and 92 million watched the Bears pound the Patriots in Super Bowl XX.
But after that, Super Bowl viewership actually decreased for a time, and that 92 million figure wasn't topped until 94 million watched the Cowboys beat the Steelers in that Super Bowl XXX.
Over the last five Super Bowls the average viewership has risen from 97 million to 98 million to 106 million to 111 million.
Finally, for the record, San Francisco and Baltimore are ranked No. 6 and No. 26, respectively, in American television markets.