The line graph plots the number of memberships (men and women separately) in a gym between 1980 and 2010.
Overall, the numbers of men varied much more than those of women, with high peaks in 1985 and 2005 and lows in 1995 and 2010. For about two-thirds of the period, 20 out of 30 years, men outnumbered the women.
In detail, the numbers of male memberships had a high of 5000 and a low of 700, compared to the much narrower (1000 to 3000) range for women. In 1980-1992 and 1999-2007, there were more men than women. Total membership in 1980 was about 3100 with 1 woman for every two men, and it rose to about 6000 in 1985, with the same gender ratio. It declined to 4600 in 1992, when there were equal numbers of men and women. Totals remained relatively constant through 1999, due to the negative correlation of the two curves. Between 1999 and 2005, memberships rose, and the total peaked around 2005-2006 at 7800—5000 men and 2900 women. After that, came a decline; there were 1900 women and 700 men in 2010.
