Since the beginning of July last year, the Government has collected an extra $263,400 from people who are penalised for not using the ACTION bus pass to "tag off" as they left the bus.

Municipal Services Minister Shane Rattenbury said 150,400 travellers had failed to tag off in the nine months, which was 1.6 per cent of people who tagged on. If you don't tag off at the end of your bus trip, you pay the full default fare of $4.50 instead of the bus-pass fare of $2.84 for a weekday trip.

The figures were provided in answer to questions from Liberal transport spokesman Alistair Coe, who questioned why passengers were being asked to tag off at all, given the city doesn't operate a zone system for bus fares, but has one fare throughout.

"Given we don't have a zonal system, tagging off is not required and therefore it seems quite heavy handed of the Government to be taking $263,000 off the relatively few people who use ACTION buses," he said. "There is no genuine fare need to tag off because it's the same fare wherever you go."

For the first year of the new bus-pass system, people were not penalised for failing to tag off. About 2.5 per cent of people failed to tag off then, when there was no penalty, compared with 1.6 per cent in the latest data.

Mr Coe said when he had asked for the average length of a bus trip a year ago, he had been told that data was not available from the system.

"If they're not extracting that what are they extracting?" he said. "If you're going to slug people for it, you should use the data."

Mr Rattenbury said My Way data was used to see where people travelled to and from, the most used routes, and how many people used particular stops – which enabled improvements to the network and prioritisation of shelters and upgrades.

While data on average travel length and time could be collated, it would be resource intensive and there was no need for the data given the flat fare structure, he said.

"When Mr Coe sought this information in 2013 he could not provide reasonable grounds for ACTION to undertake this work and it was therefore not prepared for him," Mr Rattenbury said.

Eighty per cent of passengers now used My Way cards.

In the early days of the system Government Minister Simon Corbell told an inquiry the My Way data allowed the Government to plan the network on a much more reliable basis, instead of relying on drivers to do passenger counts.

Data would be available on where people were travelling, how many were getting on at particular stops and whether people were transferring.