TATA Motors net profit more than doubled in the second quarter of the financial year,signalling a revival of buying interest in the automobile sector. The company reported a net profit of Rs 729 crore in the July-September quarter from Rs 347 crore a year earlier,a rise of 110 per cent. Increase in profits was on the back of improved margins from lower input prices,recovery in volumes and lower foreign exchange losses. The company improved its operating margin to 13.4 per cent,an improvement of 580 basis points compared with the corresponding quarter of the previous year. Volume recovery combined with improved realisations contributed to growth in revenues whilst stable material prices and accelerated cost reduction efforts continued to yield beneficial impact on margins, the company said in a statement. Total income rose 12.7 per cent to Rs 7,978.8 crore in Q2 from Rs 7,078.8 crore last year. According to industry estimates,automobile sales are expected to grow by double-digits in the year to end March. Tata Motors recorded a sales volume of 1,58,575 vehicles in the quarter (including exports),a growth of 17.4 per cent. Revival of industrial activity and improvement in liquidity coupled with introduction of new products and variants improved domestic sales. However,continued slowdown in prime markets and volatility of exchange rates persist in impacting companys exports of commercial vehicles and passenger vehicles, the company said.