MUMBAI, Jan 11 India's export-driven IT outsourcing firms are likely to raise client fees and process more work from their centres in India to cushion the impact of an increase in fees for work visas in the United States, their top market, investors said. The new U.S. measure will shave 50-60 basis points off the profit margins of information technology firms including Tata Consultancy Services and Infosys from the next fiscal year starting April 1, they said.