2004
- 44%
£1,920
2005
- 46%
£1,965
2006
- 48%
£2,168
2008
- 51%
£2,549
2009
- 53%
£2,733
2010
- 55%
£2,857
2011
- 57%
£3,091
2012
- 59%
£3,284
2013
- 61%
£3,456
2014
- 63%
£3,590
2015
- 65%
£3,693
2016
- 67%
£3,897
2017
- 69%
£4,078
2018
- 71%
£4,271
2019
- 73%
£4,417
2020
- 75%
£4,601
2021
- 77%
£4,772
2022
- 79%
£4,943
2023
- 81%
£5.114
2024
- 83%
£5,285
2004
- 44%
£1,920
2005
- 46%
£1,965
2006
- 48%
£2,168
2008
- 51%
£2,549
2009
- 53%
£2,733
2010
- 55%
£2,857
2011
- 57%
£3,091
2012
- 59%
£3,284
2013
- 61%
£3,456
2014
- 63%
£3,590
2015
- 65%
£3,693
2016
- 67%
£3,897
2017
- 69%
£4,078
2018
- 71%
£4,271
2019
- 73%
£4,417
2020
- 75%
£4,601
2021
- 77%
£4,772
2022
- 79%
£4,943
2023
- 81%
£5,114
2024
- 83%
£5,285