Analysis of council by elections 2010-2013

 Some great work by MiddleEnglander which may find useful

There were 337 seats contested in local council by-elections during 2013, including 1 where the candidate was returned unopposed. A total of 97 seats changed hands or 29% of the number contested.

The table below analyses these numbers in more detail. It also includes a comparison with not only 2012 but also 2011, when the main District Councils on a 4 year cycle held their elections, as well as 2010 when the General Election was held in May. All figures exclude deferred and delayed elections, including Exeter and Norwich in 2010.

	2013	2013	2012	2012	2011	2011	2010	2010
	Number	Changed	Number	Changed	Number	Changed	Number	Changed
England only:
- January to April	47	28%	48	40%	22	32%	41	44%
- 1st week of May, single contests	114	25%	23	13%	23	17%	38	26%
- 1st week of May, multi contests			29	17%	25	36%	45	22%
- Other May to August	56	43%	53	13%	30	37%	48	38%
- September & October	53	23%	30	37%	36	17%	58	22%
- PCC election day			34	24%
- November & December	40	33%	15	33%	26	31%	31	32%
England total	310	29%	232	25%	162	28%	261	30%
Scotland	14	43%	3	100%	18	44%	4	25%
Wales	13	8%	8	63%	12	75%	16	38%
GB total	337	29%	243	27%	192	32%	281	31%

The seats changing hands averages around 30% each year, a figure consistent with earlier studies.

In addition to these by-elections, 16 vacancies had occurred subject to the "6 month" rule, a lower figure than the 35 in 2012, 64 in 2011 and 27 in 2010 reflecting in part the number of seats being contested within the 4 year electoral cycle.  An average of 5 seats per week have fallen vacant over the last four years with some 40% or so (37% in 2013) arising from the death of a councillor.   However, on the main May election day this year, only 16% of the by-election were the result of a death with several dozen councillors elected in 2011 resigning to cause a by-election on the day of the County Council elections.