More than a third of British rail services failed to reach stations on time over the past year, according to new performance measurements.

Under the toughened standards, trains are considered punctual if they arrive within a minute of the timetable, rather than the previous limit of up to 10 minutes. Under the changed regime, just 64.7% of services were on time in the 12 months to the end of June, a figure the rail passenger watchdog Transport Focus described as “unacceptable”.

Tougher rail performance measurements show fewer than two-thirds of scheduled stops at stations were made on time, according to the Office of Rail and Road (ORR) figures.

The transport secretary, Grant Shapps, said the new way of measuring punctuality would “stop masking whether trains are really on time”.

Hull Trains had the worst punctuality record at 36.8%, followed by TransPennine Express (38.7%) and the London North Eastern Railway (41%). The best punctuality was recorded by the London-to-Essex franchise c2c (83.2%).

Under the revised standards, punctuality is recorded at every stop on a train’s route. Previously, performance was based on when a train reached its final destination.

The rail industry started to use the new measurements in July 2017 but it only became the primary assessment in April this year.

The figure of 64.7% for the 12 months to the end of June represents a year-on-year improvement of 2.5%.

Shapps said: “Commuters just want their trains to run on time and that’s my first priority. New statistics published today will stop masking whether trains are really on time. I believe this is a step in the right direction, providing more accountability and transparency to help hold operators to account, but much more needs to be done to get performance to where it should be.”

Anthony Smith, the chief executive of the Transport Focus watchdog, said passengers’ biggest priority was punctuality and “clearly one third of trains running late is not acceptable”.

He added: “Transport Focus welcomes the industry heeding its call for the figures to reflect actual arrival times rather than allowing trains up to 10 minutes late to count as ‘on time’. This will help rebuild trust in the railway.”