New data released by V/Line shows 88.1 per cent of Warrnambool line services were delivered on time in July, down 4.4 per cent from the month before.

That result falls below V/Line's punctuality target of 92 per cent, which the south-west service has exceeded just 12 times in the past decade.

The most recent occasion was in June when 92.5 per cent of trains arrived on time.

A V/Line spokeswoman said although the punctuality rate was down from the month before, it remained a significant improvement on the same time in 2018 when 81.8 per cent was recorded.

She said punctuality on the Warrnambool line hadn't dipped below 87 per cent since the completion of a $6 million package of maintenance works in early April 2019.

"Punctuality on the line has been consistently above the 12-month average since we completed a major package of improvement works in April," she said.

The spokeswoman said reliability on the Warrnambool line was 98.7 per cent in July, above the 96 per cent monthly target.

"The Warrnambool line was one of the most reliable on the network in July, with 229 of the 232 scheduled services running," she said.

Of the 229 services that operated last month, 30 were delayed by more than the nominated threshold of 10 minutes and 59 seconds.

The main reasons for delays in July included infrastructure faults, such as a defective level crossing on the Surf Coast Highway, and trespassers.

READ more: Warrnambool train line exceeds its monthly target of 92 per cent

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