Average franchise running times

This is from an old email, but I wouldn't want to lose it. Given that Superman movies always have to be so fucking long, I was curious which of the all-time great franchises (and Batman) are most distended.

Friday the 13th: 92 minutes over 12 films
Rambo: 97 minutes over 4 films (the "epic" Rambo III clocks in at 101 minutes)
PotApes: 108 minutes over 8 films (97 for the original run, 127 for the reboot trilogy)
Star Trek: 116 minutes over 13 films
Die Hard: 121 minutes over 5 films (you'd figure these were shorter, but 3 is brokenly long and 4 & 5 are modern movies)
Alien: 125 minutes over 6 films (118 if you count the AVPs)
Star Wars: 134 minutes over 8 films (surprisingly - the prequels feel so insubstantial for their >140-minute run times)
Batman: 135 minutes over 9 films (142 if you exclude the 76-minute Mask of the Phantasm)

and the winner is, naturally...
Superman: at 137 minutes over 7 films. Although it was quite a tight contest for a moment there.