What these calibrated processes cannot measure is the Singaporean motorist's mindset: the entrenched thinking that cars bought at great cost should be used to the maximum. This means the ease and comfort of driving to work and back home - and let the masses sweat it out taking public transport! A change of mindset is, in this newspaper's reckoning, the true test of ERP tinkering. Success is not to be measured solely by improved journey speeds, but also by how many car owners are converted to taking bus and rail to work as a habit. The car is reserved for family and social use in the evenings and at weekends. What will it take to convince car owners to leave their vehicles at home? More reasonably, what will persuade them to go park-and-ride? Time will tell whether the higher ERP charges and more gantries put in use will prove to be a sufficient deterrent. The record shows that most motorists have rolled with the punches, justifying to themselves that the high charges are monetary inflation. The LTA price-adjusting formula relative to journey speeds has its limits, without incurring a political cost for the Government. Can anyone conceive of a $10 ERP charge? There will be a consumer revolt.

To move more motorists onto public transport, the rail network is being expanded. This will take years. What can be done now, when road speeds have been falling, will set the tone. Park-and-ride facilities should be expanded, if physically possible, and their use eased. Steep rises in downtown parking charges dictated by demand will be a natural extension of user cost. This will make motorists think hard about driving into the city. Better rail frequencies at peak hour and lunch time, now in operation, can be improved further. Concurrent improvements in bus frequencies are also required. By the time new rail lines are ready in about 15 years, the hope must be that rail commutes will have overtaken driving as a workaday habit.