A decision by OPEC last week to maintain current levels of oil production hammered major energy companies in the U.S. and abroad.
Many energy experts had expected the group of oil-producing countries, which met in Vienna last week, to act to halt a slide in the price of crude since the summer.
A barrel of benchmark U.S. crude, which cost well above $100 as recently as June, had fallen to about $73 as of last week. OPEC announced Thursday that it would not cut production.
The effect was immediate.
The price of benchmark U.S. crude tumbled 10 percent Friday to settle at $66.15 a barrel.
Shares of companies across the energy industry fell. Chevron Corp. slid 5.4 percent, while Exxon Mobil fell 4.2 percent. Newfield Exploration fell the most among companies in the Standard & Poor’s 500 index, dropping 16.2 percent.
But the pain being felt by energy producers is proving to be a big gain for consumers and businesses that are heavily reliant on energy.
Riding high are the airlines, package-delivery services and cruise lines, which are spending less on fuel. Southwest Airlines rose 6.5 percent Friday, the most in the S&P 500 index, while Delta Air Lines Inc. was the second-biggest gainer, climbing 5.5 percent.