World oil prices declined about two percent in Tuesday's trading after Chinese oil imports slowed and a report on the U.S. economy disappointed investors.
In New York trading, the price of crude oil fell more than $2 to $79.43.
A report on declining worker productivity in the United States prompted investors to expect less demand for energy, which would lower oil prices.
The United States and China are the world's two largest oil consumers.
Some information for this report was provided by Reuters.