'Oil Goes Nonlinear'

Paul Krugman:

Oil Goes Nonlinear: When oil prices began their big plunge, it was widely assumed that the economic effects would be positive. Some of us were a bit skeptical. But maybe not skeptical enough: taking a global view, there’s a pretty good case that the oil plunge is having a distinctly negative impact. Why? ...

I believe ... there’s an important nonlinearity in the effects of oil fluctuations. A 10 or 20 percent decline in the price might work in the conventional way. But a 70 percent decline has really drastic effects on producers; they become more, not less, likely to be liquidity-constrained than consumers. Saudi Arabia is forced into drastic austerity policies; highly indebted fracking companies find themselves facing balance-sheet crises.

Or to put it differently: small oil price declines may be expansionary through usual channels, but really big declines set in motion a process of forced deleveraging among producers that can be a significant drag on the world economy, especially with the whole advanced world still in or near a liquidity trap.