Resource extraction becomes the "default sector" that still functions after other industries have come to a halt. A 2008 article by Thad Dunning argues that while resource revenues can promote or strengthen authoritarian regimes, in certain circumstances they can also promote democracy. In countries where natural resource rents are a relatively small portion of the overall economy and the non-resource economy is unequal, resources rents can strengthen democracy by reducing economic elites’ fear of ceding power since social welfare policies can be funded with resource rents and not redistribution. Dunning proposes Venezuela’s democratic consolidation during the oil boom of the 1970s as a key example of this phenomenon. A 2011 study argues that previous assumptions that oil abundance is a curse were based on methodologies which failed to take into account cross-country differences and dependencies arising from global shocks, such as changes in technology and the price of oil. The researchers studied data from the World Bank over the period 1980–2006 for 53 countries, covering 85% of world GDP and 81% of world proven oil reserves. They found that oil abundance positively affected both short-term growth and long-term income levels. In a companion paper, using data on 118 countries over the period 1970–2007, they show that it is the volatility in commodity prices, rather than abundance per se, that drives the resource curse paradox. A 2019 article by Indra Overland argues that concerns about a new form of resource curse related to renewable energy are overblown, as renewable energy resources are more evenly distributed around the world than fossil fuel resources. Some countries could still experience windfalls from critical materials for renewable energy technologies, but this depends on how the technologies evolve and which materials they require.