All but two NFC teams have made it to the Super Bowl in the past 20 years. Over 70% of teams in the NFL (23 of 32) have made it to the Super Bowl in that span, even with the recent Patriots/Colts/Steelers surge. The MLB can't boast that percentage. While we're at it, since we're using the Patriots/Colts/Steelers as a reference, it seems only fair to point out that the Yankees/Red Sox/Braves account for almost 40% of all WS appearances in the last 20 years.