Chad's service sector is limited, although it contributes an estimated 49 percent of the GDP, up from 46 percent in 1998. Privatization and improved management practices have strengthened financial services, but they remain limited in size and in the services they offer. Retail sales are conducted primarily in the informal sector. Chad holds some potential for tourism, but instability and lack of infrastructure have prevented the development of this sector. Some firms in the capital, N'Djamena, have seen a proliferation of computer service firms, offer insurance, accounting, and computer services. Several international firms offer accounting services, tax advice, and business consultancy services, but the market for these services remains limited as long as most Chadian entrepreneurs remain in the informal sector.