A key measure of U.S. inflation, the producer price index, rose more than expected in April.

The Labor Department Tuesday said prices paid to refineries, farms and factories rose six-tenths of a percent last month. That is more than investors expected. The report may indicate that inflation is growing as the U.S. economy recovers from a slowdown in growth.

Analysts say the data may prompt U.S. central bank officials to continue their program of gradually raising interest rates to fend off inflation.

Experts say those relatively low interest rates are one reason that housing starts surged 11 percent in April.

A Commerce Department report says the pace of home building picked up from about 1.8 million units per year to more than two million.

Some information for this report provided by AFP and Reuters.