Lifespan of a rock borin urchin?

[DracoKat]

I was admiring my urchin that i had for about 6-7 years now (Love this guy, extremely well behaved and never knocked anything over), and I am starting to wonder their lifespan? I can't seem to find much info on the webs about captive urchin, only those in the wild.

 

[Coralreefer1]

Usually animals that live in a captivity last longer than those found and/or living in the wild.