The one-time tax is especially unfair for old taxis, they say. Explains Shakeel Ahmed of Venus Travels, ``Cars used as commercial taxis become unusable ater five years because of the mileage they run up. So they have to be replaced. To pay a lifetime tax when the car is not used for more than five years is a losing proposition.''

Regional Transport Officer M K Hemavat, however, says the tax will be adjusted according to the age of the vehicle and the annual tax already paid on it. For instance, he says, the tax on a taxi upto two years old on April 1, 1999, will be 95 per cent of the total tax. If the vehicle is more than 14 years old, it will be 30 per cent.

The lifetime tax, Hemavat says, is calculated at the rate of 6 per cent of the price of a diesel-run vehicle and four per cent of a petrol-run vehicle's price. If no price-verifying document is produced, the tax will be charged on the basis of the current prices.

But Ashish Amin of the A D Amin and Company argues that the tax relief on old vehicles does not match the amount paid as annual tax over the years. He points out, ``At the current rates, the lifetime tax for a diesel Ambassador registered on or before April 1 is about Rs 16,800. But the figure for an old vehicle plus the road tax paid annually far exceeds this amount. This isn't fair.''

Amin says he has so far paid Rs 10,059, Rs 9,073, Rs 8,112, Rs 6,809 and Rs 4,005 in road tax on taxis purchased in 1991, 1992, 1993, 1995 and 1996 through annual installments at the rate of Rs 1,335 per annum.

The lifetime tax payable on each of these taxis, as estimated by the RTO, (after deducting the relief) comes to Rs 9,500, Rs 10,405, Rs 12,600, Rs 13,200 and Rs 15,131 respectively.

Thus, Amin ends up paying a tax of Rs 19,559 for his 1991 taxi, Rs 19,478 for his 1992 taxi, Rs 20,712 for his 1993 taxi, Rs 20,009 for his 1995 taxi and Rs 19,136 for his 1996 taxi.

While demanding that old taxis be exempt from the lifetime tax, Amin also says that operators with 10 to 90 taxis would find it extremely difficult to pay the tax in one go. ``Even those with just one taxi would be hard pressed to cough up Rs 9,000 to Rs 10,000 in one shot'', he says.

The authorities, however, do not seem to think so. Says Deputy Director (Transport) K M Makwana, ``This is the only way to realise dues from taxi-operators, who've made a habit of not paying their taxes. Most of them don't pay the road tax after the first quarter of the year required for registration.''

On the objections to the one-installment payment, he says, ``If an operator can maintain 10 to 50 taxis, why can't he pay the government its dues? All these objections are offered to avoid tax payment.''