The prices of goods and services charged by U.S. businesses rose by less than expected in May, adding to the evidence that President Trump’s tariffs are not putting upward pressure on inflation.

The producer price index for final demand ticked up 0.1 percent last month, half of what economists had forecast. Core producer prices, a metric which excludes food and energy, also rose 0.1 percent, one-third of the 0.3 percent increase forecast by economists. If trade services, a measure of retail and wholesale margins, is also excluded, prices still rose by just 0.1 percent.

Compared with a year ago, the producer price index is up 2.6 percent and the core index is up three percent. The super-core index that excludes trade services is up 2.7 percent.

The producer price index is often mistakenly referred to as a wholesale price index. Although it includes some wholesale prices, it is not particularly focused on wholesale goods. Instead, it measures prices paid to domestic producers of goods and services. The “final demand” portion signals sales to end-users of products. These include governments, foreign buyers, households, and businesses.

The index tends to track the better-known consumer price index over time, although the two can diverge from month-to-month. This month, however, they moved up at the same pace. While the consumer price index (CPI) tracks prices paid by the household sector to both foreign and domestic businesses, the producer price index (PPI) tracks prices paid by a wider group of buyers to domestic business. As a result, CPI includes the prices of imports but excludes export prices, while PPI excludes imports but includs exports.