The price of fuel has risen by almost 18 percent in a year, new figures released this afternoon show.According to the Retail Sales Index, consumer demand fell across almost all retail sectors as sales fell by more than four percent in May with the exception of service stations as sales receipts for this sector increased by 3.9 per cent. Over the last year, the cost of fuel has risen 17.9 percent.The RSI, released this afternoon, showed that sales in May declined by 4.1 percent below the $86.1 million recorded in May last year.Building material stores and liquor stores experienced the largest declines in sales of 7.9 and 7.4 percent, respectively.Residents returning to the Island declared overseas purchases of goods valued at $6.3 million during May -1.6 percent lower than the $6.4 million declared in May last year.The RSI report adds: “After adjusting for the annual retail sales rate of inflation, measured at four percent in May, the volume of retail sales fell by 7.9 percent.”Service StationsService station sales rose by 3.9 percent when compared to sales levels of May 2010. However, the higher level of sales receipts reflected more of a price increase than quantity sold. The cost of fuel during May increased 17.9 percent year-over-year.Motor Vehicle StoresRetail sales of motor vehicles fell by 2.2 percent during the year. This decline was attributed to fewer and less expensive vehicles purchased during the month of May compared to last year.Apparel StoresFor the third consecutive month, aggregate sales for apparel stores were lower. Gross revenue sales fell 3.5 percent compared to the 7.2 percent increase recorded in May 2010.All Other Store TypesDuring May 2011, the all other store types sector experienced a 5.2 percent drop in sales receipts.Pharmaceutical retailers reported the largest decline in sales within this sector with a 6.6 percent decrease. Sales by retailers of furniture, appliances and electronics also fell by 4.9 percent.Retailers of boat and marine supplies recorded the only increase within this sector, with sales increasing nearly one percent.Food and Liquor StoresGross receipts for food stores declined 4.6 percent in May 2011 when compared to the same month of the previous year. Liquor sales also decreased by 7.4 percent year-over-year.Building MaterialsReduced activity in the construction industry continued to negatively impact sales receipts for hardware and building material stores. Consumer spending dipped 7.9 percent, representing a continuous decline in sales since August 2009.Resident Purchases OverseasResident purchases overseas decreased by 1.6 percent in May 2011 compared to the previous year. Overseas purchases totalled $6.3 million, or $1 million less than the same period of 2010.WHAT IS THE RETAIL SALES INDEX?The Retail Sales Index (RSI) was first developed in 1982. It is a key economic indicator used to assess the current performance of sales activity in the retail sector of the economy.The RSI is a self-weighting index. This means that stores reporting a large value of sales have a greater impact on the movement of the index than stores reporting a low level of sales activity.The RSI serves to:1) measure monthly and annual movements of retail sales2) provide an estimated gross turnover of sales in the local retail sector3) act as a barometer of change in the level of demand for both the domestic and tourist markets