Driven by data; ridden with liberty.
The House of Commons Library is an astounding resource. Among other topics, its research papers offer a comprehensive lens of local election performance, sharing the work of local election experts Professor Rallings and Professor Thrasher .
Their work seeks to move beyond a discussion of raw counts.
The problem with simply stating raw figures – such as the vote share or the percentage of councillors won – is that local elections are not directly comparable on a year-to-year basis. Different types of councils – such as metropolitan boroughs and unitary authorities – in different parts of the country, are holding different forms of elections – either the whole council is up for election, or alternately half or a third of council seats are.
Elections where the whole council is contested are conducted every four years, meaning that we should typically look at the elections four years previously, to attempt assessing whether a party has had a good performance. In 2012, there were elections to 4,900 seats in 181 local authorities in England, Scotland and Wales, broken down by the type of local authority, quoting the House of Commons Library:
In the 2012 local election, the Conservatives won or retained control of 42 councils, a net loss of 12. The number of councils under Labour control rose by 32, from 43 to 75. The Liberal Democrats dropped their council control from seven to six, a net reduction of one.
The number of councils in no overall control (NOC) went down by 18, from 69 prior to the election, and 51 afterwards.
In the case of NOC councils, this does account for any coalitions or power-sharing agreements that may exist or later arise in those councils: it is simply the statement that no single party has a majority of councillors.
In the local election four years ago, Labour won 2,158 council seats, or 44.0% of councillors won. This was a net gain of 823 councillors. The Conservatives won 1,005 councillors, or 20.5%, and a net loss of 403 seats. The Liberal Democrats also fell in this election: with 431 councillors, 8.8% of all seats contested, and a net of loss of 333.
Like the Curtice projected national share , the Rallings & Thrasher national estimated vote share (NEVS) seeks to estimate what the vote share would have been if all the main parties – including the UK Independence Party from 2012 – had contested the council election seats. Whilst Labour’s NEVS was 24% in 2008, and hit its recorded minimum of 22% in 2009, it rose 30% in 2010 – a General Election year. The Labour NEVS rose sharply to 37% in 2011, and increased to 39% by 2012. This was by no means a peak in Labour’s local election performance, but merely a partial return to some of the glories of years past.
Whilst the total number of councillors has been steadily declining, Rallings & Thrasher also calculated the percentage of councillors by their party affiliation, reprinted in the House of Commons Library.
The Conservatives became the largest party in local government in 2003, having hit their minimum in 1996, where the party had just 19% of councillors. By 2009, 46% of all councillors were affiliated with the Conservatives.
Labour had peaked in having 48% of all local councillors in 1996 and 1997. By 2009, that had eroded down to 21%. The 2012 election restored Labour’s position to 32% of all councillors, and by 2014, that percentage would reach 35%.
The House of Commons Library should produce their report on the 2016 local elections during the next month.
 McGuinness, F., Taylor, M., and Cracknell, R., 2012. Local elections 2012. House of Commons Library. Available from: http://researchbriefings.parliament.uk/ResearchBriefing/Summary/RP12-27 [Accessed: 13th May 2016]
 Masters, A., 2016. National Equivalence. In Defence of Liberty. Available from: https://anthonymasters.wordpress.com/2016/05/13/national-equivalence/ [Accessed: 13th May 2016]