Investors struggling to predict the direction of the US sharemarket this year might be paying extra attention to the Super Bowl on Monday morning (AEDT), but strategists are sceptical of the fabled “Super Bowl Indicator”, given its growing inaccuracy.

The indicator, “discovered” by New York Times sportswriter Leonard Koppett in 1978, states that if a team from what originated as the American Football League (now known as the American Football Conference) wins, then it’s an up year for the market. If a team from the original NFL, or National Football League (now the National Football Conference) wins, then it’s supposed to be a down year.