The Labor Department announced on Tuesday the U.S. consumer price index (CPI) jumped 0.9 percent m-o-m in May, following an unrevised 0.6 percent m-o-m gain in the previous month. This was the largest one-month rise in headline CPI since June 2008.

Over the last 12 months, the CPI climbed 5.4 percent y-o-y, accelerating from +5.0 percent y-o-y reported for the period ending in May. This was the highest reading since August 2008.

Economists had forecast the CPI to increase 0.5 percent m-o-m and 4.9 percent y-o-y in the 12-month period.

According to the report, the index for used cars and trucks continued to rise sharply, surging 10.5 percent m-o-m in June. This gain accounted for more than one-third of the seasonally adjusted all items advance. Meanwhile, the food index climbed 0.8 percent m-o-m, while the energy index jumped 1.5 percent m-o-m.

The core CPI excluding volatile food and fuel costs also rose 0.9 percent m-o-m in June after an unrevised 0.7 percent m-o-m gain in the previous month.

In the 12 months through June, the core CPI surged 4.5 percent compared to an unrevised 3.8 percent advance for the 12 months ending May. This was the largest 12-month increase since November 1991.

Economists had forecast the core CPI to rise 0.4 percent m-o-m and 4.0 percent y-o-y last month.