A few weeks ago I offered some calculations suggesting that lower demand for oil might account for about $20/barrel of the dramatic decline in the price of oil since last summer. Here I point to some other evidence consistent with that conclusion.

Last week the IMF's Rabah Arezki and Olivier Blanchard produced a very useful assessment of the role of supply and demand in the recent oil price decline. They note for example that the IEA's current estimate of world oil demand growth for 2014:Q3 is 800,000 barrels/day below what the organization had been anticipating as of last June.

Source: supply and demand in the recent oil price decline.

The suddenness of this shift suggests that economic weakness in Europe, Japan, and China made a contribution. In the case of the United States, some of the long-run demand response to the price run-up of the 2000s is still underway, as seen for example in the continuing improvements in fuel economy of new cars sold in the U.S.

Average fuel economy of new passenger vehicles in miles per gallon (from EIA).

But Steve Kopits calls attention to Don Pickrell's documentation of some important long-term trends in U.S. demand as well. The American population is aging, and older people drive less.

Source: Don Pickrell's documentation.

In addition, people who don't have jobs don't drive as much. Much of the decline in the U.S. labor force participation rate seems due to long-run developments that were in evidence well before the Great Recession.

Source: due to long-run developments.

Another contributing factor to an excess supply of oil was a return of Libyan production between July and October. But the latest estimates are that some of this was lost again last month. And this weekend Libya's largest oil port was attacked, raising the possibility that more of the country's exports will again be disrupted.