In the 1970s, men were much more likely than women to be smokers - in 1974, for example, 51% of men, compared with 41% of women, smoked cigarettes. Since then, the difference in smoking prevalence between men and women has reduced, although it has not disappeared completely. This change results mainly from a combination of two factors:

• First, there is a cohort effect resulting from the fact that smoking became common among men several decades earlier than it did among women, so that in the 1970s there was a fall in the proportion of women aged 60 and over who had never smoked regularly.
• Second, men are more likely than women to have given up smoking cigarettes. It should be noted, however, that this difference conceals the fact that a proportion of men who give up smoking cigarettes remain smokers, since they continue to smoke cigars and pipes; this is much less common among women who stop smoking cigarettes.

The effect of weighting on the data suggests that the difference in prevalence between men and women may have been slightly underestimated.

• Comparison of the unweighted and weighted figures for 1998 shows the difference increased from 2 to 4 percentage points, a difference which remained similar in 2000.
• In 2000 29% of men and 25% of women were cigarette smokers.