Borders Railway bosses say they are continuing 'efforts to improve' after missing punctuality targets.
Results of the last rail four-week period from May 29 to June 25 2016 showed that only 45.5% of trains arrive at Tweedbank on time - the target is 64.8%.
But Train Operating Company ScotRail points out that the standard measure throughout Great Britain for measuring train service performance is the Public Performance Measure (PPM) - made up of punctuality and reliability.
On this measure, the results showed the showed a PPM score of 86.1% - against a target of 93%.
A ScotRail spokeswoman explained June had been a particularly difficult period on the line.
The Borders Railway that was re-opened for the first time since 1969, with 30 miles of extra track and costing £294 million is a vital commuter link between the Borders and Edinburgh.
A South of Scotland MSP, Rachel Hamilton, has been critical though, saying commuters on the line have been "consistently and persistently let down."