BUSES and trains need to recover their share as a commuting mode from passenger cars.

Transport Minister Raymond Lim said this week the Land Transport Masterplan planned to increase the proportion to 70 per cent of trips by 2020, from 59 per cent last year.

It had dropped to 63 per cent in 2004, from 67 per cent in 1997. Growing by 16 per cent from 2004 to 2008, commuting by public transport lagged the 31 per cent increase registered for car trips.

Matching the rate of increase in car usage, the number of cars on the road grew by 32 per cent in those four years.

The compounded growth rate, of about 7 per cent a year, was substantially more than the 3 per cent the Certificate of Entitlement (COE) scheme was supposed to allow. How could this go on?

The Government took drastic action to halve the permitted increase to 1.5 per cent last year, and may reduce it further in 2012 upon review. But why wasn't the excess growth reined in earlier?

The Land Transport Authority (LTA) is trying to be more accurate in predicting the number of vehicles to be scrapped, exported or otherwise taken off the road each year.

There is no perfect formula, but LTA has to sort out how and how frequently it determines COE quotas. Mr Lim favours gradual changes to give people enough time to adjust.

He thinks the car population growth rate 'should not be dependent on prevailing economic conditions, which are volatile'. He is right.

How to find a formula that takes into account the vagaries of car-buying behaviour? The record has not been encouraging.

Passenger car population growth ranged from 5 per cent to 8.9 per cent between 2005 and late 2008, but hovered at between -0.6 per cent and 3.1 per cent in the previous four years. In the current recession, we can expect people to keep their cars longer.

Fewer owners can afford to scrap them and buy new ones even in the current slow recovery.

Banks no longer offer zero down-payment loans. Fewer COEs become available. Bidding pushes prices up, as it has in recent rounds.

This helps dampen demand for new cars. As long as COE remains only a partly reliable tool, electronic road pricing will have to be depended upon to control car usage and forestall the dreaded road congestion.

Although 89.5 per cent of commuters surveyed last year found buses and trains speedy, convenient, comfortable and otherwise satisfactory, service quality must improve substantially to attract car owners, existing and prospective, to switch to public transport.

Otherwise, the authorities will continue to miss their target.

This article was first published in The Straits Times.

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