First ScotRail took over the franchise last year

The company far exceeded its target of improving punctuality by 2% each year.

First Group has made significant investment, recruited 400 staff and tightened up on reliability since it took over from National Express.

But the Rail Passengers Council said other problems across Scotland's rail network meant that people had not noticed any change.

The independent Rail Passengers Council was established to protect and represent rail users.

Scottish representative James King said: "The delays caused to trains, by failures of infrastructure, such as the catastrophic failures of the signalling at Haymarket two weeks ago and Yoker last week, are pulling Network Rail's performance right down.

"The net effect is that passengers are seeing absolutely no improvement to punctuality whatsoever."

Having enough staff has been really important in terms of our crews Mary Dickson First ScotRail

Network Rail Scotland said that over the last year it had been affected by crime and bad weather which brought floods.

Spokesman David King said: "We've just spent �18m on drainage to improve resilience to wet weather and there's far more of that to come which will make the network more consistent over the next year."

First ScotRail managing director Mary Dickson said her company's improvement in performance had been down to hard work.

She said: "Having enough staff has been really important in terms of our crews.

"And just having a dedication of saying 'this railway has to run and it has to run punctually'."