GPS tracking technology has been used to identify Perth’s most and least reliable bus routes.

Results of the analysis obtained by The Weekend West show route 379 — from Mirrabooka bus station to Ballajura shopping centre — is the city’s most reliable, being on time 97.5 per cent of the time.

The worst performer was route 160, from Terrace Road in the CBD to Fremantle train station. It ran late more than once every four trips.

Public Transport Authority spokesman David Hynes said the analysis found buses that generally travelled through the Perth CBD were most likely to run late because of traffic congestion.

The most reliable services appeared to be the feeder routes servicing suburban train stations.

Buses are considered on time if they arrive within four minutes of their schedule.

“Thanks to GPS tracking technology, we are able to monitor the on-time running of our buses very closely,” Mr Hynes said. “There are several external factors that impact bus OTR including congestion, road disruptions due to accidents and major events and roadworks being carried out.”

He said there were a number of initiatives being adopted by the PTA for more reliable travel times. They included the introduction of bus-priority initiatives such as bus lanes, bus-only turns and special traffic signals.

Work was also being done with Main Roads to give buses priority in peak periods.

Bus patronage has been declining in Perth for several years, falling below 80 million journeys in 2017-18 for the first time in seven years.

Transport consultants Steven Piotrowski and Ian Wallis — in a paper presented to the recent Australian Institute of Traffic Planning and Management’s annual conference — argued that making Perth’s bus network more efficient was a key to stopping Perth’s declining public transport use.

Services needed to be more frequent and reliable.

The Piotrowski-Wallis paper said the State Government was justifiably concerned about falling public transport patronage, especially in light of recent service expansions. But there were no easy solutions.

“The WA Government has invested billions of dollars in public transport infrastructure over the past 30 years,” the paper said.

“But during the past five years, the upward trend in public transport usage, which had been apparent since the early 1990s, has gone into reverse.”