Surging oil prices, as well as higher costs of imported equipment, caused raw material costs to increase by their highest annual rate in over 20 years in the year to July, official figures showed. The office for National Statistics revealed that input prices, on a seasonally adjusted basis, rose by 13.4 pct in July from a year earlier, up from a rise of 12.5 pct in June and well above analysts' expectations for a rise of 12.4 pct. The latest figure is the highest since the seris began in 1986. On a non-seasonally adjusted basis, input prices rose by 13.5 pct , the highest rate since February 1985, the statistics office said. On a month-on-month basis, input prices rose by 1.8 pct from June, down slightly on last month's rise of 2.6 pct but again above expectations for a more modest rise of 1.6 pct. The rise reflects rises in crude oil, imported parts and equipment prices, with only slight falls seen in fuels and home produced food prices, NS said. Crude oil prices rose by 9.0 pct between June and July and were up 57.2 pct in the year to July. This is the largest annual rise since October 2000. Imported parts and equipment prices rose 2.0 pct between June and July, partly reflecting a 3.2 pct rise in imported electronic components, including a 3.9 pct price rise in imported electronic integrated circuits and micro assemblies prices. There was also evidence, however, that manufacturers have been able to pass on some of these cost increases into their prices, which could raise concerns at the Bank of England about rising inflationary pressures ahead of Wednesday's quarterly Inflation Report. The statistics office said output prices on a non-seasonally adjusted basis rose by 0.7 pct between June and July. Analysts polled by AFX News had predicted a drop of 0.1 pct. The monthly rise suggests that the pressure on profit margins could be lessening after two months of falls in output prices in May and June. On a year-on-year basis, output prices rose by 3.0 pct, compared with a 2.5 pct rise in June, and expectations of a 2.1 pct rise. Meanwhile, core output prices, which exclude food, beverages and petroleum, rose 2.3 pct in the year to July on a seasonally adjusted basis, compared with a rise of 2.3 pct in June. Analysts had predicted a rise of 2.1 pct.