The Wall Street Journal with an article on 5 possible explanations for the turmoil in markets

  1. "The fast money moved into banks at the end of 2015 because they anticipated rate hikes, and then the fast money went out"
  2. China ... many believe will have no choice but to devalue the yuan
  3. Sovereign-Wealth Funds of oil-producing countries ... liquidating stocks "bought in happier times"
  4. Many are worried that the U.S. is about to be dragged down by global forces
  5. The slump in oil prices ... oversupply ... but a slowdown in demand as well ... "If commodities prices as a whole are generally weak, that tells me that generally speaking, global demand is weak"

There is more detail on each of those at the Wall Street Journal article, which may be gated.

Any more anyone would like to add?

Even the tin hats if you're out there; you know, global plot by the lizard people etc. Have at it!