LONDON (Reuters) – Britain’s statistics office said on Monday it had underestimated the pace of growth in costs in the labour market, one of the pieces of data that the Bank of England is looking at as it considers whether to raise interest rates next month.

Annual growth in unit labour costs – the cost to employers to produce a given amount of output – stood at 2.4 percent in the second quarter, the ONS said on Monday, not 1.6 percent as it had announced on Friday. The ONS said it made an error in its original calculations.

Unit labour costs rose by 3.5 percent in the first quarter and the growth of 2.4 percent in the second was the slowest since the first three months of 2016, the revised ONS figures showed.

The BoE is expected to announce on Nov. 2 that it is raising interest rates for the first time in more than a decade.