Projected National Share
Projected National Share is a statistic used in British politics. It refers to the translation of local election results to reflect national party support in a future general election. PNS shows which party has won a local election. The numbers give an impression of how the political parties are faring if the entire country cast a local ballot. PNS can be calculated in different ways.
History
BBC News has calculated PNS since 1982. They use key wards which are reflective of the country as a whole in order to calculate party share. Two academics at the University of Plymouth, Colin Rallings and Michael Thrasher, calculate National Equivalent share using a different approach.Author and peer Mark Pack maintains a historical record named LocalBase of both sets of results.