US wholesale inflation accelerated sharply in September, reaching its highest annual level since December 2022, as soaring energy costs and a steep jump in gasoline prices pushed producer prices higher, according to data released by the US Bureau of Labour Statistics (BLS) on Thursday.The Producer Price Index (PPI), which measures the prices domestic producers receive for goods and services, climbed 1.3 per cent month-on-month in September. This was its steepest monthly increase since March 2022 and marked a significant acceleration from the previous two months. On a year-on-year basis, producer prices rose 6.3 per cent, highlighting the growing pressure on businesses across the US economy. The latest reading exceeded the annual increases recorded in July and August, pointing to a renewed pickup in wholesale price pressures. The September increase marks a significant development in the US inflation outlook, with the annual rise in producer prices reaching a level last seen in December 2022. The BLS said, "On an unadjusted basis, the index for final demand climbed 6.3 per cent for the 12 months ended in September, the largest 12-month increase since moving up 6.4 per cent in December 2022." The monthly pace of wholesale inflation also strengthened considerably. The PPI rose 0.5 per cent in August and 0.2 per cent in July before jumping 1.3 per cent in September. The latest data suggest that inflationary pressures have intensified, with the increase extending across several categories of goods and services rather than being limited to a single segment. Energy was the biggest contributor to the September increase, with prices for final demand goods rising 2.6 per cent during the month. According to the BLS, this was the largest monthly gain since the series began in December 2009. The agency noted, "Over 80 per cent of the broad-based rise in September is attributable to the index for final demand energy, which jumped 10.8 per cent." Gasoline prices surged 20.3 per cent, accounting for half of the monthly increase in goods prices. Other energy-related categories, including diesel fuel, jet fuel, residential electricity and crude petroleum, also recorded price increases. Food prices climbed 1.2 per cent in September. Meanwhile, goods prices excluding food and energy rose 0.3 per cent, indicating that price increases were not confined entirely to volatile energy and food categories. The increase in wholesale prices was also evident in the services sector. Prices for final demand services rose 0.8 per cent in September, adding to concerns that inflationary pressures are spreading across the economy. The BLS stated, "Nearly half of the broad-based September increase can be attributed to a 1.4-per cent rise in margins for final demand trade services." Transportation and warehousing services recorded an even sharper increase, with prices rising 3.4 per cent during the month. Higher costs in these areas can affect businesses that depend on shipping, logistics and distribution, potentially adding to their operating expenses. The services data indicate that the September inflation increase was supported by more than just higher fuel costs, with trade-related margins and transportation expenses also contributing. A separate measure of producer inflation, which excludes food, energy and trade services, increased 0.5 per cent in September. This was faster than the 0.3 per cent rise recorded in August.