Source: Office for National Statistics
Notes on cigarette smoking prevalence data
1. Weighted data are only available from 2000 onwards.
2. Data on cigarette use were collected on a 2-yearly basis prior to 2000.
3. Estimates prior to 2005 are based on a fiscal year rather than a calendar year.
4. Estimates for 2004 and 2005 both include the period 1 January 2005 to 31 March 2005 as a result of a change in survey period from a fiscal year to a calendar year.
5. Estimates for 2006 to 2011 include longitudinal data.
6. Weighted bases are given to the nearest thousand.
More information about the data used and sample sizes can be found on the above links.
The Office for National Statistics ‘Adult smoking habits in the UK: 2016’ statistical bulletin provides information on cigarette smoking among adults including the proportion of people who smoke including demographic breakdowns, changes over time, and e-cigarettes.