The graph presents the proportion of four categories of household waste that were recycled in a certain city over the period from 1992 to 2002. What stands out from the graph is that the rates for recycled glass, paper, and cans experienced noticeable growth within the given timeframe, while the figure for plastic recycling showed almost no increase. By 2002, the recycling rate for glass had become the highest among the four categories.
The percentage of glass recycling started at 14% in 1992, then doubled to 28% by 1997. It continued to rise steadily, reaching approximately 48% in the final year.
The proportion of paper recycling showed a somewhat similar upward trend. It began at 14%, then surged to around 31% in 1997, and finally peaked at just under 40% by 2002.
On the other hand, the recycling rate of cans, which was the highest among the categories in 1992 at 18%, dropped to 13% by 1997. Despite this initial decline, it rose again to 24% in 2002.
Finally, the figure for plastic recycling saw only a slight increase over the period. In 1992, it stood at around 10%, rose marginally to 12% in 1997, and maintained a similar level up to 2002.