The U.S. Commerce Department released the producer price index figures on Friday. The U.S. producer price index increased 0.5% in May, exceeding expectations for a 0.4% gain, after a 0.4% drop in April. It was the largest increase since September 2012.

On a yearly basis, the producer price index decreased 1.1% in April, in line with expectations, after a 1.3% fall in April.

The rise was driven by higher food and gasoline prices. Gasoline prices jumped 17.0% in May, the largest rise since August 2009. Food prices climbed by 0.8%, driven by a shortage of eggs, and as wholesale egg prices jumped a 56.4% in May.

The producer price index excluding food and energy climbed 0.1% in May, in line with expectations, after a 0.2% decrease in April.

On a yearly basis, the producer price index excluding food and energy climbed 0.6% in May, missing forecasts of a 0.7% increase, after a 0.8% rise in April.

The figures added to speculation on that the Fed will start raising its interest rate this year.