The10 per cent income tax surcharge is expected to yield the government Rs 750 crore (Rs 7.50 billion).

Finance Minister Jaswant Singh levied an impost of 3 paise a rupee in the Budget for 2003-04 on incomes over Rs 8.5 lakh a year.

Revenue department officials said the idea was to target non-salary income through the surcharge.

A recent study by the department has shown flexible income earners outnumber wage earners in the income brackets of Rs 5-10 lakh a year and over Rs 10 lakh.

While 22,568 salary income assessees earned over Rs 10 lakh in 2001-02, 35,568 non-salary income assessees did the same that year.

Similarly, in the Rs 5-10 lakh bracket, the 1,53,287 non-salary income assessees were 45,000 more than the salary income assessees in that tax slab. But the tax department is targeting more flexible income assessees.

High-salary assessees accounted for 1.45 per cent of the total number of returns filed. In the case of high non-salary income assessees, it was 1.42 per cent.

"Approximately, 80 per cent the salary income assessees earn less than Rs 2 lakh a year," a revenue department official said.