How often do comets survive passage by the Sun? I had heard that comet ISON might not survive a close pass by our Sun, and I was curious about the odds of how other comets had fared. So, how often do other comets survive a close pass by our sun? Also, are there any connections between a comet's size or buildup(of material) that makes it more or less likely to not survive?
Key factors:


How close is perihelion? Too close and it may be destroyed on its first pass. We know Halley's Comet, which has a perihelion of about 0.6AU, has been orbiting for over 2000 years, passing the sun every 74-76 years and is still going strong.
How big is it? Every pass loses material, so a bigger comet could last longer.
What is its composition? Darker comets can absorb more energy when close to the sun, which may accelerate outgassing and breakup.


And of course some comets hit large objects - Shoemaker-Levy hit Jupiter and was destroyed.