Super Bowl XLII: Still Not Bigger Than M*A*S*H

So Super Bowl XLII capped a magnificent back-to-back run for the NFL and its fans, with the second straight last-minute touchdown finish in a row and America's team — yeah, I said it, Dallas doesn't have six rings, and I'm a '9ers fan:( — The Pittsburgh Steelers took home the top prize.
This year's Super Bowl drew more than 94 million viewers, second all-time to last year's game, which drew more than 97 million. Yet both still fall well short of the M*A*S*H finale, which drew 105 million viewers — in 1983!
What gives? I mean, I'm a big fan of Hawkeye, Radar, Klinger and Hot Lips Houlahan as anyone, and I was 6 at the time, so I'm definitely old enough to remember the last M*A*S*H, but bigger than the past two Super Bowls? 25+ years later?
And hat was going on in 1983 that the entire television watching universe had nothing better to do than watch the last episode of M*A*S*H?
I suppose the answer is an obvious nothing.