Also check this out:
http://blog.strava.com/the-chariot-o...vs-price-1835/

Strava only reports VAM for cat 3 and harder climbs, so OP you need to find some longer climbs to ride to get more VAM data.

I really like VAM as a metric. It's interesting to me that I can generate higher VAMs as the road gets steeper, even though I'm riding more slowly, for instance I've got to ~1300 when the road is >10% but on sustained 5-7% ish climbs, I'm happy to break into the 1000-1100 range.