Over 100 million are expected to watch the big game this year, but they won’t just be tuning in for the football. 

Over 100 million are expected to watch the big game this year, but they won’t just be tuning in for the football. All eyes will also be on Super Bowl Sunday’s ads. So, how did America’s most-heralded sporting event become the most desired 30-second spot on television? Here’s a look at the history of Super Bowl commercials.

In 2011, NBC, CBS, and Fox paid $1 billion each for the event’s broadcast rights, switching off year to year for the next nine years. The networks can expect to recoup about $250 million of that in ad sales for each big game it airs.

The first Super Bowl was played in 1967. Back then, it aired on two networks, NBC and CBS. NBC charged companies $75,000 for a 60-second spot, while CBS charged $85,000. A 30-second spot cost $42,000, which is worth about $316,000 today.

By Super Bowl 14, the year of Mean Joe Greene’s famous Coca-Cola commercial, a 30-second spot fetched $222,000.

In Super Bowl 18, Apple aired their blockbuster ‘1984’ ad. The ad itself cost about $370,000 to produce, but that year, the average 30-second spot cost $525,000. It was a worthwhile investment by Apple, as the commercial was reportedly seen by 85 million people and continues to rank as one of the most famous ads in Super Bowl history.

A 30-second spot crossed the million-dollar threshold in Super Bowl 29 and would hit $2 million only five years later.

Come Super Bowl 50, 30 seconds would cost companies $4.5 million and the broadcast would garner 112 million viewers.

This year, ads are selling north of $5 million, thanks to an increase in ratings for this season’s NFL games. At that price, the nation’s top brands certainly hope you won’t mute your TVs during Super Bowl timeouts.