Shoppers spent less in December than November, says BRC However, December also saw a record 19.2pc growth in online purchases. Britain's economy has recovered strongly this year with annualised growth of 3pc in the three months to September. But the Bank of England and other economists are concerned about the sustainability of the recovery. Its main driver, household spending, has been funded by reduced savings while wages have been rising at less than half the rate of inflation. BRC figures are based on sales in cash terms, rather than the inflation-adjusted measures that will feed into official fourth-quarter gross domestic product data due on January 28. Normally inflation would mean that the volume increase in retail sales is lower than the increase in sales values. But earlier this week the BRC reported that high street prices in December were 0.8pc lower than a year earlier. This means that the increase in retail sales volumes was probably higher than the 2.2pc annual rise in sales values reported by the BRC for the fourth quarter of 2013. The Office for National Statistics said that in the three months to November, retail sales volumes excluding automotive fuel were 2.5pc up on a year earlier.