Ask HN: How much would you pay for verified salary information?

Kicking around an idea after the recent salary posts, what would you pay for aggregate salary information by metro area and by employer?

Employers share salary information via third parties, check out imercer.com. they tout nearly 150k engineering salaries across 1500 employers alone. If you work for an employer of any size they are most definitely contributing your salary information to this database to be used in negotiations with you.

So why not have a similar system where we have verified compensation data coming from employees? Self reported salaryou websites aren't reliable and you are pretty much laughed at if you bring those data sources to the negotiation table.

The engineering report costs $3k, I'm thinking $5 per head for monthly access and you also need to verify your compensation (tbd). Thoughts?