Oil prices rose for the fourth day in a row Thursday December 22, 2011 amid signs of an improving U.S. economy and concerns about global supplies.

The price of benchmark crude rose 86 cents to finish at $99.53 per barrel in New York. At one point in the session it hit $100.05. Brent crude, which is used to price crude produced in many foreign countries and is important for U.S. gasoline producers, rose 18 cents to end at $107.89 per barrel in London.

A series of positive reports in the U.S. suggested that the economy is slowly improving. That has sent stock prices and oil prices higher this week.