Feature Request: Auto-clear of Security History

After a (preferably user-configurable) amount of time, NAV should clear the Security History automatically. I recently discovered that I had several years worth (several gigabytes) of Security History sitting on my disk. It's not obvious that users should go and periodically clean this out, and even if it were obvious, it's an unnecessary pain in the butt to do. It's pretty reasonable to assume that Security History entries older than a month aren't going to be referred to anymore.