Prior to the current Deepwater Horizon oil spill in the Gulf of Mexico, the number of spills from offshore oil rigs and pipelines in U.S. waters more than quadrupled from 2000-2009, according to a report by USA Today. USA Today”s analysis shows the spills — and the amount of oil that leaked — grew markedly worse even when taking increases in production into account.

USA Today reports that from the early 1970s through the ”90s, offshore rigs and pipelines averaged about four spills per year of at least 50 barrels, according to the Minerals Management Service (MMS). One barrel is equal to 42 gallons. USA Today says the average annual total rose to more than 17 from 2000 through 2009, with spills averaging 22 a year from 2005 to 2009.

USA Today reports that MMS data shows the company with the most spills from 2000 through 2009 is BP, which reported 23 spills of 50 barrels or more. Oil firm Shell was next with 21 spills of 50 barrels or more.

To read the full USA Today report on this story, click here.