Yeah, about .25% per year
So if you have a 20 panel system, say
300W each = 6000 W and that's 15W lost per year. Over 20 years,
that's 300W, so you effectively loss the output equal to one panel.
on equipment and lighting is increasing faster than .25% per year, so
unless you increase your load, you will never have a problem.
And the system is warranted for 25 years, and will probably last 40, there are no moving parts.