discovering I had visited one in 2000, I visited a site in Canada, one in the UK, one in Holland, and three in Korea. Six is my biggest haul since 2003, when I made it to a ridiculous eight.
My total is now at 54 out of 936, or 5.8%. It's up about two percentage points in the last six years. I did some quick estimates recently, and I think I'll top out in the 10-15% range some day, but that day does not appear to be anywhere close to hand.
If in 2012, I go to the same conferences as I did this year, I can rent a car on my free afternoon and drive to Canterbury, and then see how many of Beijing's six world heritage sites I can cram into a 4-day trip. On the other hand, it's a lot harder to travel with toddlers at home, so 2012 may see the percentage slide back towards five percent as more sites are added.