Seven years, We were using a pool service and though I can't prove it I'm sure they put lots more chemicals in than were necessary. The liner became brittle and started cracking last fall. Also the pool liner was faded almost white BELOW the waterline. Another factor could be that our old marble gray liner was only offered one year so it might have been a color issue.It does look great! I'm curious... Maybe I missed it, but how old was the liner you were replacing?