Leopards Changing Spots?

It is a fairly common maxim that a leopard never changes its spots, meaning that the very nature of a leopard is such that it will always look the same.  A little closer to home, in the finance business we tend to cite that someone is statistically more likely to get divorced than change their bank account.  In the interest of assessing the likelihood of certain things happening, I was wondering to myself “how often do constituencies change party hands?”

Snow leopard licking its paw

Snow leopard – also not known for changing their spots.

The answer to this was not easy to find.  There are records of elections on the Office for National Statistics website spanning back to 1918, but oddly enough there didn’t seem to be a dataset focusing on changes in party affiliation.  The data is definitely out there, but it doesn’t seem to be easily accessible.

I decided therefore to do some legwork myself to answer that question.

Methodology

I started with a raw document outlining the votes received in each constituency between 1918 and today.  From this, I applied a lookup function which matched the largest proportion to the column header for that party, which allowed me to easy work out the winning party for each constituency.

I then used ChatGPT to produce a list of constituency creation dates.  I have checked some of these, but not all, so this is a definite area of uncertainty.

The final step was to create another lookup function to check the winner in an election year and identify whether the winner was different in a previous year.  Due to the difficulty of including by-elections, this table only looks at the results during a General Election, so if party A was replaced by party B in a by-election, but then by party A again at the next General Election, this data would assume continuous loyalty to party A.

The Data - "How Often do Constituencies Change Party Hands?"

After analysing the data, I came up with the following table of results, so here’s the answer to the question “how often do constituencies change party hands?”:

Constituency2019 WinnerLast Changed InCreated In
ABERAVONLabourNever1918
ABERCONWYConservativeNever2010
ABERDEEN NORTHSNP20151885
ABERDEEN SOUTHSNP20191885
AIRDRIE AND SHOTTSSNP20152005
ALDERSHOTConservativeNever1918
ALDRIDGE-BROWNHILLSConservative19791974
ALTRINCHAM AND SALE WESTConservativeNever1997
ALYN AND DEESIDELabourNever1983
AMBER VALLEYConservative20101983
ANGUSSNP20191708
ARFONPlaid CymruNever2010
ARGYLL AND BUTESNP20152005
ARUNDEL AND SOUTH DOWNSConservativeNever1997
ASHFIELDConservative20191955
ASHFORDConservativeNever1885
ASHTON-UNDER-LYNELabourNever1885
AYLESBURYConservativeNever1553
AYR, CARRICK AND CUMNOCKSNP20192005
BANBURYConservativeNever1553
BANFF AND BUCHANConservative20171945
BARKINGLabourNever1945
BARNSLEY CENTRALLabourNever1983
BARNSLEY EASTLabourNever1983
BARROW AND FURNESSConservative20191983
BASILDON AND BILLERICAYConservativeNever2010
BASINGSTOKEConservativeNever1885
BASSETLAWConservative20191885
BATHLiberal Democrats20171295
BATLEY AND SPENLabour19971983
BATTERSEALabour20171885
BEACONSFIELDConservativeNever1974
BECKENHAMConservativeNever1974
BEDFORDLabour20171295
BELFAST EASTDUP20151885
BELFAST NORTHSinn Fein20191885
BELFAST SOUTHSDLP20191885
BELFAST WESTSinn Fein20011885
BERMONDSEY AND OLD SOUTHWARKLabour20151983
BERWICKSHIRE, ROXBURGH AND SELKIRKConservative20171553
BERWICK-UPON-TWEEDConservative20152005
BETHNAL GREEN AND BOWLabour20101997
BEVERLEY AND HOLDERNESSConservativeNever1997
BEXHILL AND BATTLEConservativeNever1997
BEXLEYHEATH AND CRAYFORDConservative20051983
BIRKENHEADLabourNever1885
BIRMINGHAM, EDGBASTONLabourNever1950
BIRMINGHAM, ERDINGTONLabourNever1955
BIRMINGHAM, HALL GREENLabourNever1955
BIRMINGHAM, HODGE HILLLabourNever1983
BIRMINGHAM, LADYWOODLabourNever1974
BIRMINGHAM, NORTHFIELDConservative20191955
BIRMINGHAM, PERRY BARRLabourNever1974
BIRMINGHAM, SELLY OAKLabourNever1955
BIRMINGHAM, YARDLEYLabour20151950
BISHOP AUCKLANDConservative20191885
BLACKBURNLabour19451885
BLACKLEY AND BROUGHTONLabourNever2010
BLACKPOOL NORTH AND CLEVELEYSConservativeNever1997
BLACKPOOL SOUTHConservative20191997
BLAENAU GWENTLabour20101983
BLAYDONLabourNever1983
BLYTH VALLEYConservative20191950
BOGNOR REGIS AND LITTLEHAMPTONConservativeNever1997
BOLSOVERConservative20191950
BOLTON NORTH EASTConservative20191983
BOLTON SOUTH EASTLabourNever1983
BOLTON WESTConservative20151983
BOOTLELabour19451885
BOSTON AND SKEGNESSConservativeNever1997
BOSWORTHConservativeNever1983
BOURNEMOUTH EASTConservativeNever1950
BOURNEMOUTH WESTConservativeNever1950
BRACKNELLConservativeNever1983
BRADFORD EASTLabour20151885
BRADFORD SOUTHLabour19511950
BRADFORD WESTLabourNever1885
BRAINTREEConservative20051974
BRECON AND RADNORSHIREConservative20151983
BRENT CENTRALLabour20152010
BRENTFORD AND ISLEWORTHLabour20151974
BRENT NORTHLabour19971950
BRENTWOOD AND ONGARConservativeNever1974
BRIDGENDConservative20191983
BRIDGWATER AND WEST SOMERSETConservativeNever2010
BRIGG AND GOOLEConservative20101997
BRIGHTON, KEMPTOWNLabour20171950
BRIGHTON, PAVILIONGreen20101950
BRISTOL EASTLabour19921885
BRISTOL NORTH WESTLabour20171950
BRISTOL SOUTHLabour19351885
BRISTOL WESTLabour20151885
BROADLANDConservativeNever1983
BROMLEY AND CHISLEHURSTConservativeNever1997
BROMSGROVEConservativeNever1918
BROXBOURNEConservativeNever1983
BROXTOWEConservative20101983
BUCKINGHAMConservative20191885
BURNLEYConservative20191885
BURTONConservative20101885
BURY NORTHConservative20191983
BURY SOUTHConservative20191983
BURY ST EDMUNDSConservativeNever1553
CAERPHILLYLabourNever1983
CAITHNESS, SUTHERLAND AND EASTER ROSSLiberal Democrats20172005
CALDER VALLEYConservative20101983
CAMBERWELL AND PECKHAMLabourNever1983
CAMBORNE AND REDRUTHConservativeNever2010
CAMBRIDGELabour20151295
CANNOCK CHASEConservative20101997
CANTERBURYLabour20171918
CARDIFF CENTRALLabour20151983
CARDIFF NORTHLabour20171950
CARDIFF SOUTH AND PENARTHLabourNever1950
CARDIFF WESTLabour19871983
CARLISLEConservative20101295
CARMARTHEN EAST AND DINEFWRPlaid Cymru20011997
CARMARTHEN WEST AND SOUTH PEMBROKESHIREConservative20101997
CARSHALTON AND WALLINGTONConservative20191997
CASTLE POINTConservative20011983
CENTRAL AYRSHIRESNP20152005
CENTRAL DEVONConservativeNever1997
CENTRAL SUFFOLK AND NORTH IPSWICHConservativeNever1983
CEREDIGIONPlaid Cymru20171983
CHARNWOODConservativeNever1983
CHATHAM AND AYLESFORDConservative20101997
CHEADLEConservative20151983
CHELMSFORDConservativeNever1295
CHELSEA AND FULHAMConservativeNever1997
CHELTENHAMConservative20151997
CHESHAM AND AMERSHAMConservativeNever1974
CHESTERFIELDLabour20101918
CHICHESTERConservativeNever1295
CHINGFORD AND WOODFORD GREENConservativeNever1974
CHIPPENHAMConservative20151983
CHIPPING BARNETConservativeNever1885
CHORLEYOther20191983
CHRISTCHURCHConservativeNever1997
CITIES OF LONDON AND WESTMINSTERConservativeNever1950
CITY OF CHESTERLabour20151545
CITY OF DURHAMLabourNever1950
CLACTONConservative20172010
CLEETHORPESConservative20101997
CLWYD SOUTHConservative20191983
CLWYD WESTConservative20051983
COATBRIDGE, CHRYSTON AND BELLSHILLSNP20192005
COLCHESTERConservative20151885
COLNE VALLEYConservative20191885
CONGLETONConservativeNever1983
COPELANDConservative20171983
CORBYConservative20101983
COVENTRY NORTH EASTLabourNever1974
COVENTRY NORTH WESTLabourNever1974
COVENTRY SOUTHLabourNever1974
CRAWLEYConservative20101983
CREWE AND NANTWICHConservative20191997
CROYDON CENTRALLabour20171974
CROYDON NORTHLabourNever1997
CROYDON SOUTHConservativeNever1955
CUMBERNAULD, KILSYTH AND KIRKINTILLOCH EASTSNP20152005
CYNON VALLEYLabourNever1983
DAGENHAM AND RAINHAMLabourNever2010
DARLINGTONConservative20191918
DARTFORDConservative20101950
DAVENTRYConservativeNever1983
DELYNConservative20191983
DENTON AND REDDISHLabourNever1983
DERBY NORTHConservative20191950
DERBYSHIRE DALESConservativeNever1950
DERBY SOUTHLabourNever1983
DEVIZESConservativeNever1918
DEWSBURYConservative20191983
DONCASTER CENTRALLabourNever1983
DONCASTER NORTHLabourNever1983
DON VALLEYConservative20191983
DOVERConservative20101918
DUDLEY NORTHConservative20191997
DUDLEY SOUTHConservative20101983
DULWICH AND WEST NORWOODLabourNever1997
DUMFRIES AND GALLOWAYConservative20172005
DUMFRIESSHIRE, CLYDESDALE AND TWEEDDALEConservativeNever2005
DUNDEE EASTSNP20051950
DUNDEE WESTSNP20151983
DUNFERMLINE AND WEST FIFESNP20151983
DWYFOR MEIRIONNYDDPlaid CymruNever2010
EALING CENTRAL AND ACTONLabour20152010
EALING NORTHLabourNever1950
EALING, SOUTHALLLabourNever1974
EASINGTONLabourNever1950
EAST ANTRIMDUP20051885
EASTBOURNEConservative20191950
EAST DEVONConservativeNever1983
EAST DUNBARTONSHIRESNP20192005
EAST HAMLabourNever1885
EAST HAMPSHIREConservativeNever1983
EAST KILBRIDE, STRATHAVEN AND LESMAHAGOWSNP20152005
EASTLEIGHConservative20151955
EAST LONDONDERRYDUP20011885
EAST LOTHIANSNP20191997
EAST RENFREWSHIRESNP20192005
EAST SURREYConservativeNever1983
EAST WORTHING AND SHOREHAMConservativeNever1997
EAST YORKSHIREConservativeNever1885
EDDISBURYConservativeNever1997
EDINBURGH EASTSNP20152005
EDINBURGH NORTH AND LEITHSNP20151997
EDINBURGH SOUTHLabour19871885
EDINBURGH SOUTH WESTSNP20152005
EDINBURGH WESTLiberal Democrats20171885
EDMONTONLabour19971918
ELLESMERE PORT AND NESTONLabourNever1997
ELMET AND ROTHWELLConservativeNever1983
ELTHAMLabour19971974
ENFIELD NORTHLabour20151974
ENFIELD, SOUTHGATELabour20171950
EPPING FORESTConservativeNever1974
EPSOM AND EWELLConservativeNever1885
EREWASHConservative20101983
ERITH AND THAMESMEADLabourNever1997
ESHER AND WALTONConservativeNever1997
EXETERLabourNever1997
FALKIRKSNP20152005
FAREHAMConservativeNever1983
FAVERSHAM AND MID KENTConservativeNever1997
FELTHAM AND HESTONLabourNever1997
FERMANAGH AND SOUTH TYRONESinn Fein20171950
FILTON AND BRADLEY STOKEConservativeNever2010
FINCHLEY AND GOLDERS GREENConservative20101997
FOLKESTONE AND HYTHEConservativeNever1918
FOREST OF DEANConservative20051983
FOYLESDLP20191983
FYLDEConservativeNever1983
GAINSBOROUGHConservative19241885
GARSTON AND HALEWOODLabourNever2010
GATESHEADLabourNever2010
GEDLINGConservative20191983
GILLINGHAM AND RAINHAMConservativeNever2010
GLASGOW CENTRALSNP20151885
GLASGOW EASTSNP20152005
GLASGOW NORTHSNP20152005
GLASGOW NORTH EASTSNP20192005
GLASGOW NORTH WESTSNP20152005
GLASGOW SOUTHSNP20152005
GLASGOW SOUTH WESTSNP20152005
GLENROTHESSNP20152005
GLOUCESTERConservative20101295
GORDONSNP20191885
GOSPORTConservativeNever1997
GOWERLabour20171885
GRANTHAM AND STAMFORDConservativeNever1983
GRAVESHAMConservative20051983
GREAT GRIMSBYConservative20191918
GREAT YARMOUTHConservative20101295
GREENWICH AND WOOLWICHLabourNever1997
GUILDFORDConservative20051885
HACKNEY NORTH AND STOKE NEWINGTONLabourNever1950
HACKNEY SOUTH AND SHOREDITCHLabourNever1950
HALESOWEN AND ROWLEY REGISConservative20101983
HALIFAXLabour19871983
HALTEMPRICE AND HOWDENConservativeNever1997
HALTONLabourNever1983
HAMMERSMITHLabourNever1885
HAMPSTEAD AND KILBURNLabourNever2010
HARBOROUGHConservativeNever1983
HARLOWConservative20101983
HARROGATE AND KNARESBOROUGHConservative20101997
HARROW EASTConservative20101950
HARROW WESTLabour19971945
HARTLEPOOLLabourNever1974
HARWICH AND NORTH ESSEXConservativeNever2010
HASTINGS AND RYEConservative20101983
HAVANTConservativeNever1983
HAYES AND HARLINGTONLabour19971950
HAZEL GROVEConservative20151997
HEMEL HEMPSTEADConservative20051974
HEMSWORTHLabourNever1983
HENDONConservative20101945
HENLEYConservativeNever1983
HEREFORD AND SOUTH HEREFORDSHIREConservativeNever1983
HERTFORD AND STORTFORDConservativeNever1983
HERTSMEREConservativeNever1983
HEXHAMConservativeNever1983
HEYWOOD AND MIDDLETONConservative20191983
HIGH PEAKConservative20191885
HITCHIN AND HARPENDENConservativeNever1997
HOLBORN AND ST PANCRASLabourNever1983
HORNCHURCH AND UPMINSTERConservativeNever2010
HORNSEY AND WOOD GREENLabour20151983
HORSHAMConservativeNever1983
HOUGHTON AND SUNDERLAND SOUTHLabourNever2010
HOVELabour20151950
HUDDERSFIELDLabour19451885
HUNTINGDONConservativeNever1983
HYNDBURNConservative20191983
ILFORD NORTHLabour20151950
ILFORD SOUTHLabour19921945
INVERCLYDESNP20152005
INVERNESS, NAIRN, BADENOCH AND STRATHSPEYSNP20152005
IPSWICHConservative20191295
ISLE OF WIGHTConservative20011832
ISLINGTON NORTHLabour19451885
ISLINGTON SOUTH AND FINSBURYLabourNever1974
ISLWYNLabourNever1983
JARROWLabour19551885
KEIGHLEYConservative20191885
KENILWORTH AND SOUTHAMConservativeNever1997
KENSINGTONConservative20191950
KETTERINGConservative20051918
KILMARNOCK AND LOUDOUNSNP20152005
KINGSTON AND SURBITONLiberal Democrats20171997
KINGSTON UPON HULL EASTLabourNever1950
KINGSTON UPON HULL NORTHLabourNever1950
KINGSTON UPON HULL WEST AND HESSLELabourNever1950
KINGSWOODConservativeNever2010
KIRKCALDY AND COWDENBEATHSNP20192005
KNOWSLEYLabourNever1983
LAGAN VALLEYDUP20051983
LANARK AND HAMILTON EASTSNP20152005
LANCASTER AND FLEETWOODLabour20152010
LEEDS CENTRALLabour19451885
LEEDS EASTLabourNever1885
LEEDS NORTH EASTLabour19971885
LEEDS NORTH WESTLabour20171885
LEEDS WESTLabour19871885
LEICESTER EASTLabour19871974
LEICESTER SOUTHLabour19871983
LEICESTER WESTLabourNever1974
LEIGHConservative20191885
LEWESConservative20151950
LEWISHAM, DEPTFORDLabourNever1974
LEWISHAM EASTLabour19921974
LEWISHAM WEST AND PENGELabourNever1974
LEYTON AND WANSTEADLabourNever1997
LICHFIELDConservativeNever1997
LINCOLNConservative20191295
LINLITHGOW AND EAST FALKIRKSNP20152005
LIVERPOOL, RIVERSIDELabourNever1983
LIVERPOOL, WALTONLabourNever1950
LIVERPOOL, WAVERTREELabourNever1997
LIVERPOOL, WEST DERBYLabourNever1950
LIVINGSTONSNP20151983
LLANELLILabourNever1918
LOUGHBOROUGHConservative20101983
LOUTH AND HORNCASTLEConservativeNever1997
LUDLOWConservative20051983
LUTON NORTHLabour19971950
LUTON SOUTHLabour19971950
MACCLESFIELDConservativeNever1918
MAIDENHEADConservativeNever1997
MAIDSTONE AND THE WEALDConservativeNever1997
MAKERFIELDLabourNever1983
MALDONConservativeNever1997
MANCHESTER CENTRALLabourNever1918
MANCHESTER, GORTONLabourNever1918
MANCHESTER, WITHINGTONLabour20151918
MANSFIELDConservative20171885
MEON VALLEYConservativeNever2010
MERIDENConservative19791950
MERTHYR TYDFIL AND RHYMNEYLabourNever1983
MID BEDFORDSHIREConservativeNever1997
MID DERBYSHIREConservativeNever1983
MIDDLESBROUGHLabourNever1974
MIDDLESBROUGH SOUTH AND EAST CLEVELANDConservative20171997
MID DORSET AND NORTH POOLEConservative20151997
MIDLOTHIANSNP20192005
MID NORFOLKConservativeNever1983
MID SUSSEXConservativeNever1997
MID ULSTERSinn Fein20011950
MID WORCESTERSHIREConservativeNever1983
MILTON KEYNES NORTHConservativeNever1997
MILTON KEYNES SOUTHConservativeNever1997
MITCHAM AND MORDENLabour19971974
MOLE VALLEYConservativeNever1974
MONMOUTHConservative20051918
MONTGOMERYSHIREConservative20101885
MORAYConservative20171885
MORECAMBE AND LUNESDALEConservative20101997
MORLEY AND OUTWOODConservative20152010
MOTHERWELL AND WISHAWSNP20151983
NA H-EILEANAN AN IARSNPNever1918
NEATHLabourNever1983
NEWARKConservative20011885
NEWBURYConservative20051997
NEWCASTLE-UNDER-LYMEConservative20191918
NEWCASTLE UPON TYNE CENTRALLabour19871918
NEWCASTLE UPON TYNE EASTLabour19451885
NEWCASTLE UPON TYNE NORTHLabour19511918
NEW FOREST EASTConservativeNever1997
NEW FOREST WESTConservativeNever1997
NEWPORT EASTLabourNever1918
NEWPORT WESTLabour19871918
NEWRY AND ARMAGHSinn Fein20051885
NEWTON ABBOTConservativeNever1997
NORMANTON, PONTEFRACT AND CASTLEFORDLabourNever1983
NORTHAMPTON NORTHConservative20101974
NORTHAMPTON SOUTHConservative20051997
NORTH ANTRIMDUPNever1885
NORTH AYRSHIRE AND ARRANSNP20152005
NORTH CORNWALLConservative20151997
NORTH DEVONConservative20151950
NORTH DORSETConservativeNever1983
NORTH DOWNAlliance20191885
NORTH DURHAMLabourNever1885
NORTH EAST BEDFORDSHIREConservativeNever1997
NORTH EAST CAMBRIDGESHIREConservativeNever1997
NORTH EAST DERBYSHIREConservative20171885
NORTH EAST FIFELiberal Democrats20191983
NORTH EAST HAMPSHIREConservativeNever1997
NORTH EAST HERTFORDSHIREConservativeNever1997
NORTH EAST SOMERSETConservativeNever1997
NORTH HEREFORDSHIREConservativeNever1885
NORTH NORFOLKConservative20191950
NORTH SHROPSHIREConservativeNever1983
NORTH SOMERSETConservativeNever1997
NORTH SWINDONConservative20101997
NORTH THANETConservativeNever1983
NORTH TYNESIDELabourNever1983
NORTH WARWICKSHIREConservative20101997
NORTH WEST CAMBRIDGESHIREConservativeNever1997
NORTH WEST DURHAMConservative20191885
NORTH WEST HAMPSHIREConservativeNever1983
NORTH WEST LEICESTERSHIREConservative20101983
NORTH WEST NORFOLKConservative20011997
NORTH WILTSHIREConservativeNever1983
NORWICH NORTHConservative20101983
NORWICH SOUTHLabour20151983
NOTTINGHAM EASTLabour19921885
NOTTINGHAM NORTHLabour19871950
NOTTINGHAM SOUTHLabour19921955
NUNEATONConservative20101885
OCHIL AND SOUTH PERTHSHIRESNP20192005
OGMORELabourNever1918
OLD BEXLEY AND SIDCUPConservativeNever1997
OLDHAM EAST AND SADDLEWORTHLabourNever1997
OLDHAM WEST AND ROYTONLabourNever1997
ORKNEY AND SHETLANDLiberal Democrats19921918
ORPINGTONConservative19701945
OXFORD EASTLabour19871983
OXFORD WEST AND ABINGDONLiberal Democrats20171983
PAISLEY AND RENFREWSHIRE NORTHSNP20152005
PAISLEY AND RENFREWSHIRE SOUTHSNP20152005
PENDLEConservative20101983
PENISTONE AND STOCKSBRIDGEConservative20192010
PENRITH AND THE BORDERConservativeNever1983
PERTH AND NORTH PERTHSHIRESNPNever2005
PETERBOROUGHConservative20191918
PLYMOUTH, MOOR VIEWConservative20152010
PLYMOUTH, SUTTON AND DEVONPORTLabour20172010
PONTYPRIDDLabourNever1918
POOLEConservativeNever1950
POPLAR AND LIMEHOUSELabourNever2010
PORTSMOUTH NORTHConservative20101950
PORTSMOUTH SOUTHLabour20171918
PRESELI PEMBROKESHIREConservative20051997
PRESTONLabour19451295
PUDSEYConservative20101983
PUTNEYLabour20191918
RAYLEIGH AND WICKFORDConservativeNever1997
READING EASTLabour20171983
READING WESTConservative20101983
REDCARConservative20191974
REDDITCHConservative20101983
REIGATEConservativeNever1955
RHONDDALabourNever1885
RIBBLE VALLEYConservativeNever1983
RICHMOND PARKLiberal Democrats20191885
RICHMOND (YORKS)ConservativeNever1997
ROCHDALELabour20101918
ROCHESTER AND STROODConservativeNever2010
ROCHFORD AND SOUTHEND EASTConservativeNever1997
ROMFORDConservative20011885
ROMSEY AND SOUTHAMPTON NORTHConservativeNever1997
ROSSENDALE AND DARWENConservative20101983
ROSS, SKYE AND LOCHABERSNP20152005
ROTHERHAMLabour19351918
ROTHER VALLEYConservative20191918
RUGBYConservative19791885
RUISLIP, NORTHWOOD AND PINNERConservativeNever1974
RUNNYMEDE AND WEYBRIDGEConservativeNever1997
RUSHCLIFFEConservativeNever1983
RUTHERGLEN AND HAMILTON WESTSNP20192005
RUTLAND AND MELTONConservativeNever1983
SAFFRON WALDENConservativeNever1974
SALFORD AND ECCLESLabourNever2010
SALISBURYConservativeNever1295
SCARBOROUGH AND WHITBYConservative20051997
SCUNTHORPEConservative20191918
SEDGEFIELDConservative20191974
SEFTON CENTRALLabourNever2010
SELBY AND AINSTYConservativeNever2010
SEVENOAKSConservativeNever1950
SHEFFIELD, BRIGHTSIDE AND HILLSBOROUGHLabourNever2010
SHEFFIELD CENTRALLabour19451885
SHEFFIELD, HALLAMLabour20171885
SHEFFIELD, HEELEYLabourNever1950
SHEFFIELD SOUTH EASTLabourNever2010
SHERWOODConservative20101983
SHIPLEYConservative20051983
SHREWSBURY AND ATCHAMConservative20051997
SITTINGBOURNE AND SHEPPEYConservative20101997
SKIPTON AND RIPONConservativeNever1983
SLEAFORD AND NORTH HYKEHAMConservativeNever1997
SLOUGHLabour19971983
SOLIHULLConservative20151945
SOMERTON AND FROMEConservative20151983
SOUTHAMPTON, ITCHENConservative20151950
SOUTHAMPTON, TESTLabourNever1918
SOUTH ANTRIMDUP20171885
SOUTH BASILDON AND EAST THURROCKConservativeNever2010
SOUTH CAMBRIDGESHIREConservativeNever1997
SOUTH DERBYSHIREConservative20101983
SOUTH DORSETConservative20101885
SOUTH DOWNSinn Fein20171885
SOUTH EAST CAMBRIDGESHIREConservativeNever1983
SOUTH EAST CORNWALLConservative20101983
SOUTHEND WESTConservativeNever1950
SOUTH HOLLAND AND THE DEEPINGSConservativeNever1997
SOUTH LEICESTERSHIREConservativeNever1983
SOUTH NORFOLKConservativeNever1983
SOUTH NORTHAMPTONSHIREConservativeNever2010
SOUTHPORTConservative20171885
SOUTH RIBBLEConservative20101983
SOUTH SHIELDSLabour19351832
SOUTH STAFFORDSHIREConservativeNever1997
SOUTH SUFFOLKConservativeNever1983
SOUTH SWINDONConservative20101997
SOUTH THANETConservative20101983
SOUTH WEST BEDFORDSHIREConservativeNever1997
SOUTH WEST DEVONConservativeNever1997
SOUTH WEST HERTFORDSHIREConservativeNever1950
SOUTH WEST NORFOLKConservativeNever1997
SOUTH WEST SURREYConservativeNever1950
SOUTH WEST WILTSHIREConservativeNever1918
SPELTHORNEConservativeNever1997
STAFFORDConservative20101885
STAFFORDSHIRE MOORLANDSConservative20101950
ST ALBANSLiberal Democrats20191974
STALYBRIDGE AND HYDELabourNever1997
ST AUSTELL AND NEWQUAYConservative20152010
STEVENAGEConservative20101974
ST HELENS NORTHLabourNever1974
ST HELENS SOUTH AND WHISTONLabourNever2010
STIRLINGSNP20192005
ST IVESConservative20151918
STOCKPORTLabour19921832
STOCKTON NORTHLabourNever2010
STOCKTON SOUTHConservative20192010
STOKE-ON-TRENT CENTRALConservative20191950
STOKE-ON-TRENT NORTHConservative20191950
STOKE-ON-TRENT SOUTHConservative20171950
STONEConservativeNever1997
STOURBRIDGEConservative20101997
STRANGFORDDUP20011885
STRATFORD-ON-AVONConservativeNever1885
STREATHAMLabour19921918
STRETFORD AND URMSTONLabourNever1997
STROUDConservative20191950
SUFFOLK COASTALConservativeNever1983
SUNDERLAND CENTRALLabourNever2010
SURREY HEATHConservativeNever1997
SUTTON AND CHEAMConservative20151945
SUTTON COLDFIELDConservativeNever1945
SWANSEA EASTLabour19221918
SWANSEA WESTLabour19451918
TAMWORTHConservative20101997
TATTONConservative20011983
TAUNTON DEANEConservative20151997
TELFORDConservative20151997
TEWKESBURYConservativeNever1997
THE COTSWOLDSConservativeNever1997
THE WREKINConservative19791918
THIRSK AND MALTONConservativeNever1997
THORNBURY AND YATEConservative20152010
THURROCKConservative20101983
TIVERTON AND HONITONConservativeNever1997
TONBRIDGE AND MALLINGConservativeNever1983
TOOTINGLabourNever1974
TORBAYConservative20151983
TORFAENLabourNever1983
TORRIDGE AND WEST DEVONConservative20051983
TOTNESConservativeNever1997
TOTTENHAMLabourNever1950
TRURO AND FALMOUTHConservativeNever2010
TUNBRIDGE WELLSConservativeNever1885
TWICKENHAMLiberal Democrats20171950
TYNEMOUTHLabourNever1997
UPPER BANNDUP20051983
UXBRIDGE AND SOUTH RUISLIPConservativeNever2010
VALE OF CLWYDConservative20191997
VALE OF GLAMORGANConservative20101983
VAUXHALLLabourNever1950
WAKEFIELDConservative20191832
WALLASEYLabour19921918
WALSALL NORTHConservative20171950
WALSALL SOUTHLabourNever1950
WALTHAMSTOWLabour19921950
WANSBECKLabourNever1983
WANTAGEConservativeNever1983
WARLEYLabourNever1997
WARRINGTON NORTHLabourNever1983
WARRINGTON SOUTHConservative20191983
WARWICK AND LEAMINGTONLabour20171997
WASHINGTON AND SUNDERLAND WESTLabourNever1997
WATFORDConservative20101945
WAVENEYConservative20101983
WEALDENConservativeNever1983
WEAVER VALELabour20171997
WELLINGBOROUGHConservative20051950
WELLSConservative20151918
WELWYN HATFIELDConservative20051983
WENTWORTH AND DEARNELabourNever1918
WEST ABERDEENSHIRE AND KINCARDINEConservative20171997
WEST BROMWICH EASTConservative20191974
WEST BROMWICH WESTConservative20191974
WEST DORSETConservativeNever1885
WEST DUNBARTONSHIRESNP20152005
WEST HAMLabourNever1885
WEST LANCASHIRELabourNever1885
WESTMINSTER NORTHLabourNever2010
WESTMORLAND AND LONSDALELiberal Democrats20051983
WESTON-SUPER-MAREConservative20051950
WEST SUFFOLKConservativeNever1997
WEST TYRONESinn Fein20011997
WEST WORCESTERSHIREConservativeNever1997
WIGANLabourNever1918
WIMBLEDONConservative20051918
WINCHESTERConservative20101918
WINDSORConservativeNever1997
WIRRAL SOUTHLabourNever1997
WIRRAL WESTLabour20151997
WITHAMConservativeNever2010
WITNEYConservativeNever1983
WOKINGConservativeNever1950
WOKINGHAMConservativeNever1955
WOLVERHAMPTON NORTH EASTConservative20191950
WOLVERHAMPTON SOUTH EASTLabourNever1974
WOLVERHAMPTON SOUTH WESTConservative20191950
WORCESTERConservative20101918
WORKINGTONConservative20191918
WORSLEY AND ECCLES SOUTHLabourNever1997
WORTHING WESTConservativeNever1997
WREXHAMConservative20191918
WYCOMBEConservativeNever1950
WYRE AND PRESTON NORTHConservativeNever1997
WYRE FORESTConservative20101983
WYTHENSHAWE AND SALE EASTLabourNever1997
YEOVILConservative20151983
YNYS MONConservative20192010
YORK CENTRALLabour19921983
YORK OUTERConservativeNever2010

Importantly, this data shows that of the 650 current constituencies, 295 (45.38%) have either never changed party hands or have not changed hands since 1918.

How might we fix this? With my favourite proposal – Proportional Representation.