Disclaimer — I do not presume to know what will happen to the global economy in 2016 and you should be very skeptical of those who think they do know.
Hardly a day passes now without turmoil in the world's financial markets. Oil prices have yet to find the bottom, which tells us that there's not much demand for the stuff. And yet, when we look at the data, we are told that oil (liquids) demand grew in 2015, and that it's expected to rise some more in 2016.
Perhaps supply has outstripped (still growing?) demand, but that certainly doesn't imply that crude oil should be trading at the ultra-low price of $28/barrel.
What the fuck?