A report by the International Monetary Fund (IMF) this week highlighted the damage sub-$50/barrel oil can do to an oil producer's economy.
Two relatively minor producers, Brunei and Equatorial Guinea have spent the last five years in recession, the IMF reported. It also mentioned a trio of bigger producers whose economies have contracted for the last three years – Libya, Yemen and Venezuela.
Oil prices, however, only partially explain why these countries are faring so badly economically.
Most have deep structural problems. Libya and Yemen are still politically unstable after decades of corrupt leadership and civil unrest, while Venezuela's populist social spending destroyed economic growth and resulted in hyperinflation.
Meanwhile, the impact of low oil prices on an economy that has been in recession for five years is misleading, since prices only started their fall to current levels in mid-2014.
Oil remains, however, the most valuable export of all these countries, and next month the leaders of the 13-nation oil cartel – the Organisation of Petroleum Exporting Countries ( OPEC) – meet.
They will discuss what can be done to prop up prices and alleviate the pain being felt by some of their members.
"There was a time when the oil price equation was relatively simple," says Graham Smith at Fidelity.
He explains: "OPEC decided how much oil would be supplied to the world and consumers and industry decided how much they could afford or wanted to buy. The balance between the two produced the oil price."
The 2008 oil spike
This balance, most memorably, became a large imbalance in 2008 as rapidly-growing China's massive appetite for energy conflicted with fears of dwindling supply and pushed the price of Nymex WTI to a record high of $147.27 a barrel.
Predictions of "peak oil" – reaching maximum global output, then entering decline – being reached within the next couple of decades only backed up the case for high prices.
Some analysts believed we'd never see $50/barrel oil again. Goldman Sachs even predicted a "superspike" up to and beyond $200/barrel.
The shale revolution
OPEC, as representative of two-fifths of global output, could smooth oil prices by lowering or raising its output – depending on whether it considered market prices too high or too low. But the emergence of a new breed of producers changed this dynamic.