How well do political parties retain their vote?

So How well have the main three parties retained their vote since the last General Election?

http://cdn.yougov.com/cumulus_uploads/document/ubu9k3q6xe/YG-Archive-Pol-Sunday-Times-results-09-110813.pdf

YOU GOV POLLING Where the Lib Dem vote from #GE2010 has gone LibDems 35% Labour 33% Conservatives 15% Green 8% UKIP 6% SNP/PLAID 1%
— General Election (@UKELECTIONS2015) August 11, 2013

YOU GOV POLLING Where the Conservative vote from #GE2010 has gone Conservatives 74% UKIP 16% Labour 6% LibDem 1% SNP/PLAID 1% BNP 1%
— General Election (@UKELECTIONS2015) August 11, 2013

YOU GOV POLLING Where the Labour vote from #GE2010 has gone Labour 89% UKIP 4% Conservative 2% Lib Dem 2% snp/plaid 1% GREEN 1%
— General Election (@UKELECTIONS2015) August 11, 2013