Government has fixed the base price at Rs 145 per share for 9.5 per cent stake sale in National Thermal Power Corporation. The government proposes to sell 78.32 crore shares or 9.5 per cent stake in the country's largest power producer through offer for sale (OFS) route. The auction will take place today. Earlier the Empowered Group of Ministers, headed by Finance Minister P Chidambaram, had decided on the floor price and date of the share sale.