East Coast rail had the most late-running trains last month, according to figures from Network Rail.
East Coast was able to run only 82.8% of trains on time, making it the poorest-performing train operator.
Across all train companies, a total of 91.4% of trains ran on time in the period March 3 to March 31, compared with 93.4% for the same period last year.
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The Met Office has issued a yellow cold weather alert and there's the risk of snow in places later on Boxing Day.
Mostly dry and bright, but chilly. Frost tonight.
Most places will see bright or sunny spells through the day, but with a few showers around, especially during the morning.