Retail sales continue to boom with the latest data showing that they are up more than 20 per cent year on year. The May figures for the Retail Sales Index were released yesterday along with new vehicle licensing data for April, are further evidence that the economy is coming dangerously close to overheating. There were 27,148 new cars licensed in April compared to 18,190 a year ago. In the first four months of the year there were 106,794 cars licensed, an increase of 43 per cent on the same period last year. There were also significant increases in sales of pharmaceuticals and cosmetics - up 23.5 per cent - and textiles and clothing - up 20.8 per cent.