Natural gas supplies have expanded tremendously following a boom in North American production. The government says they're now more than 40 percent higher than the five-year average.

Here are key statistics about U.S. natural gas supplies and prices.

_ TOTAL SUPPLY: 2.6 trillion cubic feet.

_ AVERAGE SUPPLY: 1.9 trillion cubic feet.

_ PRICE: On Thursday, natural gas fell by 2.2 cents to $2.621 per 1,000 cubic feet, down 32 percent from a year ago.