Psephology.AI

    Election Health and Fragmentation

    How competitive local elections are: choice on the ballot, uncontested seats, winners' shares and how many parties really compete.

    Count each contest: For each ward contest we count candidates and seats. A seat is uncontested when no more candidates stood than there were seats.

    Winner's share and majority: Measured in single-seat wards only, because shares in multi-seat wards are not comparable.

    Fragmentation: The effective number of parties is 1 divided by the sum of each party's squared vote share, averaged across contested wards.

    Compare: Each figure is compared with the latest earlier year that has the same measure.

    All insights

    Insight 10

    Election Health and Fragmentation

    How competitive local elections are: choice on the ballot, uncontested seats, winners' shares and how many parties really compete.

    Provisional, 1973 onwards

    For every year of scheduled local elections since 1973: candidates per seat, seats nobody contested, the average winner's share and majority, the effective number of parties, turnout, and women standing and elected.

    Loading election health figures…

    What the report does

    A year-by-year health check of local democracy, with six headline tiles, trend charts and the record highs and lows.

    How it's built

    1. 1

      Count each contest

      For each ward contest we count candidates and seats. A seat is uncontested when no more candidates stood than there were seats.

    2. 2

      Winner's share and majority

      Measured in single-seat wards only, because shares in multi-seat wards are not comparable.

    3. 3

      Fragmentation

      The effective number of parties is 1 divided by the sum of each party's squared vote share, averaged across contested wards.

    4. 4

      Compare

      Each figure is compared with the latest earlier year that has the same measure.

    How to read it (and how not to)

    • • By-elections are left out; they appear in the By-election Vote Tracker.
    • • Gender is known for only a small share of candidates.
    • • Sitting-councillor records are not yet loaded, so re-election rates are not shown yet.
    • • Years with patchy records are excluded from records (fewer than 50 contests).

    What it reads

    • • Every scheduled local election result from 1973
    • • Seats available in each ward
    • • Candidate gender and sitting-councillor flags where recorded

    What you get back

    • • Six headline tiles per year
    • • Trend charts for every measure
    • • Record highs and lows

    Readiness

    • Local election results

      Used directly.

    • Sitting-councillor flags

      Expected from Elections Centre handbooks and Democracy Club.

    Live figures are held back until these are in place; no estimated numbers are shown in the meantime.