The given line graph illustrates the proportion of children across four distinct age cohorts in the United Kingdom over an 11-year period from 1990 to 2001.
Overall, it is conspicuous that the 10-14 and 5-9 age brackets experienced an overall upward trend, with the former becoming the most dominant group by the end of the timeframe. Conversely, the figures for the remaining two younger and older groups underwent a net decline, consistently lagging behind their counterparts.
Looking at the details, the percentage of adolescents aged 15-19 commenced the period at the highest position of 26.1%. However, this figure plummeted dramatically to 23.2% in 1993 before staging a steady recovery to 25.0% by 2001. A somewhat inverse pattern was observed in the youngest cohort (0-4); their proportion initially rose from roughly 26.0% to a peak of 25.5% in 1992, but subsequently entered a stable downward trajectory, finishing at a period-low of 23.6%.
By contrast, the 10-14 age group started at the lowest point of 23.1% in 1990. This demographic registered a gradual but continuous expansion, ultimately overtaking all other groups to peak at 26.2% in the final year. Meanwhile, the figure for children aged 5-9 stood at 24.6% at the beginning, climbed moderately to 26.1% in 1997, and thereafter decreased constantly to close at 25.1% in 2001.