In recent years, the United States has experienced large increases in oil production due in large part to a new technology, hydraulic fracturing ("fracking"). Fracking involves injecting a mixture of water, sand, and chemicals into rock formations at high pressure to release oil and natural gas. An article in the Wall Street Journal indicates that economies of scale in fracking may be considerably smaller than in conventional oil drilling. If this view is correct, what would the likely consequences be for the number of firms drilling for oil in the United States?