Like everyone else here, I also think that Salary as a basis for a metric doesn't make sense in a lot of ways. But on the other hand, you can't expect someone that makes $30K a year to have the same benchmark as someone who makes $100K a year. So it's just a better gauge than nothing but age, right?
If you kind of want to see where your NW stands, a site like networthshare.com might be of use. You can browse people's net worth by age, income, line of work, etc. I think most of the NWs there are above average as you are comparing your NW to a bunch of people that care to track their net worth. But it's still a fun site and I like to use it to get a snapshot of my NW monthly. Yes, I also use aggregator sites like personal capital, but there's something reassuring about the habit of updating it manually every month and putting in my little comment...