COLUMBUS, Ohio - Oil prices have hit levels not seen in more than three years and retail gasoline prices are below $2 in nearly half of the country, according to The Associated Press.

Oil prices Thursday fell as low as $49.75 a barrel, levels last seen on May 18, 2005, when oil was at $46.80 a barrel.

Light, sweet crude for December delivery is still down $2.64, nearly 5 percent at $50.98 a barrel on the New York Mercantile Exchange.

Meanwhile, prices at the pump fell again overnight to nearly $2 a gallon and are now down more than 50 percent in just four months when they reached a record $4.11 in July.