Last? A few years ago it was reported that there are 30 million people living in caves in China and more cavemen on Earth now than at any point in history.
This New York Times article is specific to a naturally-occurring cave big enough to fit an entire village of wooden houses and then some.
I'm not saying you're wrong. Just trying to explain the discrepancy.
[0] http://articles.latimes.com/2012/mar/18/world/la-fg-china-ca...