This article stresses the importance of looking at your net worth at least once a year. It also presents statistics to which you can compare yourself, based on your age range and income range.
I’m doing pretty well for my age range, but a bit far behind for my salary range. Considering I’ve only been at this salary level for a year and a half, it’s not so bad.
The article also links to a handy net worth calendar that can assist you if you’re calculator or Excel deficient.