Bouyed by the 7.9 per cent GDP growth in the 2nd quater, the Finance Minister Mr Pranab Mukherjee has expressed the hope that the economy will grow stronger in October-March period. Addressing the CEOs conference on Globalisation and Inclusive growth in New Delhi , he said that the biggest challenge of the economy is to return to the 9 per cent growth rate. The minister said that the 7.9 percent growth in the country's economy in the September quarter is the fastest in 18 months. He said that India's reform process have been deliberate and slow but are irreversible. The minister said that the industry and services sectors have emerged the main drivers on the event of slowdown in agriculture due to weak monsoon. The main thrust of the economy, Mr Mukherjee said, is improving the efficiency and efficacy of the tax system and expanding tax base.