I think strictly indoor cats tend to live a little longer.....for obvious reasons like no outside dangers (cars, other animals, etc.). But indoor only cats can get sick just like any other pet can so being inside doesn't always guarantee safety.

I had a cat who lived to be 21. Got her when I was in first grade and she lived until after I was married and moved out.

I have a cat right now that is 12. One that is 10 and one that is 8. The 10 year old cat was just dx with lymphoma. He's on Prednisone plus an anti-nausea med but otherwise seems content.

Some cats live as long as 25 years but I think that is extremely elderly for a cat.

Thank you for providing a loving home for your kitty for the last 16 years, Kicker. It's a big responsibility taking care of a pet. They depend on us for everything.