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The 49ers were pretty good in the 80s and 90s

Posted by Doug on November 22, 2006

A few days ago I told you about the 49ers' run of 285 straight games without a three-game losing streak. It lasted from week 1 of 1981 until week 7 of 1999.

During that time, San Francisco went 210-74-1, for a winning percentage of .739. Suppose you had a coin that came up heads 73.9 percent of the time. If you flipped it 285 times, what are the chances that you'd see a run of three straight tails in there at some point? About 98.4%, it turns out.

Football teams are not coins, of course. I'm not sure if the things that make football teams different from coins would generally make streaks more likely or less likely. On the one hand, there is some artificial balancing created by the schedule. Teams rarely play more than two consecutive games on the road or at home, for instance. On the other hand, if you believe in teams getting hot or going through slumps, then that would make football teams more prone to streaks than coins are. Even if you don't believe in those things, injuries probably make teams streakier than coins. In any event, I'm convinced that 1.6% is a decent estimate of a team's chances of putting together a run like that, given that they're as good as the 1981--1999 Niners.

So, while unlikely, it's not that crazy that the 49ers, as good as they were during that stretch, never lost three straight. No, the crazy part is that they were that good for that long. Take a look at the records of the other NFL franchises during that same period of time.


TM Record PCT
========================
sfo 210- 74-1 0.739
mia 175-108-1 0.618
den 174-110-1 0.612
was 164-119-1 0.579
jax 40- 30-0 0.571
dal 162-122-0 0.570
pit 158-127-0 0.554
nyg 156-127-2 0.551
chi 155-130-0 0.544
oak 155-130-0 0.544
min 155-130-0 0.544
kan 153-129-2 0.542
buf 153-132-0 0.537
gnb 147-135-2 0.521
phi 140-142-3 0.496
sea 138-146-0 0.486
nor 135-149-0 0.475
cle 111-125-1 0.470
car 32- 37-0 0.464
nwe 132-153-0 0.463
sdg 130-154-0 0.458
ten 130-155-0 0.456
nyj 127-156-2 0.449
det 125-158-1 0.442
stl 125-159-0 0.440
cin 123-162-0 0.432
atl 112-172-1 0.395
ari 111-172-2 0.393
ind 102-181-1 0.361
bal 18- 34-1 0.349
tam 97-187-0 0.342

The difference betwen San Francisco and #2 is bigger than the difference between #2 and #15. They were nearly two wins per year better than anybody else for an 18-year period.

This entry was posted on Wednesday, November 22nd, 2006 at 6:07 am and is filed under General, History. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.