Explaining the reason for the changes, Prof Charles Pattie, an expert on the process based at the University of Sheffield, said redrawing boundaries ensured elections were fair and designed to give every potential vote equal value.
“If one constituency has more electors than another, then the views of individual voters in the smaller constituency count more than those of voters in the larger one which would not be fair,” he said.
“Over time, local populations change and they do so at different rates in different places.
“So every so often constituencies are redrawn to ensure they have more or less equal electorates.
“At present, the law requires that constituencies are redrawn every eight years.
“With a very few unusual exceptions, virtually all constituencies have to have electorates within plus or minus five per cent of 73,393 registered voters.”
According to the Boundary Commission only eight fell within the permitted range, with five below – Barnsley Central, Barnsley East, Rotherham, Sheffield Heeley and Sheffield South East – while Sheffield Central fell above the range.
