They didn't lay any eggs this year, but laid about 6 last year. They don't lay very often when they get old.
Most of mine kicked the bucket at about 11 or 12. Some died younger. I had a silkie hen that died at 14 last winter.
Some literally drop dead - of apparent stroke or heart attack. My large silkie rooster was found dead under his perch in the morning. Some die of cancer. I've had a few hens get ovarian cancer which was determined by the vet. (Whenever a chicken starts a slow decline, I make sure it's nothing contagious). The vet said that ovarian cancer in animals that ovulate as often as a chicken isn't surprising.