A spokesman for Southern trains said:
"Southern achieved improved scores in many of the categories, but we are disappointed that our overall satisfaction score hasn’t risen.
"We recognise that performance is a key driver to achieving passenger satisfaction and for much of the survey period, general railway infrastructure problems and a particularly difficult leaf fall season made it a particularly challenging period for us. We operate around 2,300 trains each weekday on one of the country’s most congested networks where knock-on effects from one small incident can cause major problems.
"We are analysing the results and will be working hard on a plan to improve in the areas where our passengers tell us we need to."
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