Jumped Timing Chain?

I appreciate everyone's replies. I have determined, just by reading the posts, that it probably hasn't jumped a tooth. Most likely it has stretched, but it is a little older, and I'm sure it has stretched without running any of the tests mentioned, it is not running with the power it had, and there is no reason on earth it would need 5 degrees more advance than it did for the previous 5 years it has been in the motor all the sudden. It does not ping under heavy acceleration in 3rd up a hill. It starts perfect when hot, and runs cool. I did put a new distributor in it, same deal, 5 degrees more advanced. I will first try the "back up the crank and see how long it takes to move the rotor in the distributor" test. Then I will run a compression test. If it fails that one, then I will be putting a much better chain in than stock. I'll go run those two tests now. They are free and easy.