I’ve spent most of today gathering together some data about Liberal Democrat Parliamentary seats for my dissertation, and figured that some of you might find it interesting.

The data set is Liberal Democrat seats won at a general election or by-election since 1992, so it excludes pre-1992 seats won at by-elections (which in practice means no Ribble Valley) and seats held by defectors, unless they were won at a subsequent election. I’ve tried to keep some continuity between seats when the geography remains roughly similar – I’ve treated the various Inverness and Nairn seats as one, for instance – but in some cases that’s not been possible.

There are 81 seats that have been won by the party since 1992. 60 of them were originally won from Conservatives (including 6 at by-elections and one defection), 20 from Labour (including 5 at by-elections and one via defection from Labour to the SDP) and one from Plaid Cymru.

There are currently eight held seats: the longest continually-held seat is Orkney and Shetland (since 1950), the others have all been won since 1997. Carshalton and Wallington, Sheffield Hallam and Southport were all won then, North Norfolk in 2001, and Ceredigion, Leeds North West and Westmorland & Lonsdale in 2005. Ceredigion is a bit of a special case as it was previously held by Liberals from 1979 to 1992 and for most of the period up until 1966.

Of the other 73 seats: as of 2015, 41 are now held by the Conservatives with Liberal Democrats in second place in 35 of those seats, third in 2, fourth in 3 and fifth in the Isle of Wight. Labour hold 16 with Liberal Democrats second in 9, third in 2, fourth in 4 and fifth in Leicester South. The SNP hold 11 with Liberal Democrats in second place in 8 seats, third place in 2 seats and fourth place in Dunfermline and West Fife.

The other five seats have been split up too much to have a single recognisable successor seat: Liverpool Mossley Hill (now all in Labour-held constituencies), Tweeddale, Ettrick and Lauderdale (now in SNP or Conservative constituencies), Truro, Teignbridge, and Falmouth & Camborne (the latter three now all in Conservative constituencies)

I’m not drawing too many conclusions from this yet – part of the reason for doing this is just to have the information I need in one place so I can use it more easily – but there are some interesting patterns in the data. Seats gained from Conservatives tend to follow the pattern of the party having been in 2nd place for a long period – in all the gains from Conservatives since 1997, the party was in 2nd place at the 1992 election. Gains from Labour are much more complex – in 1992, Liberal Democrats were second in four seats that were subsequent gains from Labour, but only one of those (Chesterfield) was won by Labour at that election. Liberal Democrats were second to the Conservatives in three (Bristol West, Leeds North West, and Falmouth & Camborne) that Labour would win in 1997, but the Liberal Democrats would go on to win in 2005. In all four of the 2010 gains from Labour (Bradford East, Burnley, Norwich South, and Redcar), Liberal Democrats were third in 1992, 1997 and 2001, before moving up to second in 2005.

It’s all interesting grist for my theoretic mill about the effects of the structure of competition within the party system, but hopefully some of you will find the information of use for its own sake.