the table below describes the proportion of smokers in males and females

The table shows the how the percentage of smokers in both two genders changes during the span of 1970 and 2000 in Britain. The proportion of male and female smokers raised and fell nearly at the same time. To elaborate, between 1970 and 1990 smokers increased by almost 30 percent. And the rebound in 1990 showed a moderate contraction to 28 percent in 2000 from 37 percent in the peak. In 1970, the proportion of smokers is the lowest number among the seven records, while the males’ percentage is twice as females’ counterparts, at 10% and 5% respectively. The year of 1975 witnessed a sudden increase of males’ smokers to a twofold figure, and in 1980 both percentages climbed 13% and 9% respectively. The number for male smokers increased steadily and reach the peak at 37% in 1985. Then, there was a sudden decrease in a decade, from 36% to 28%.