I've paid 5% into out retirement for 33 years, and could technically retire (quit and do something else) with a pension of approximately 30% of what I make now. No health care. That's okay through...it's growing exponentially now.
It's what you take out that matters, not what you pay in. 5% ain't much considering the stock market just recovered from the 2000/1 downturn.
However, regardless of that you have a defined benefit pension and not a 401K system that pays a defined benefit regardless of what was paid in and regardless of what it's earned, or hasn't.