The line graph illustrates data on 3 sources of air pollutants in the UK during the period 1990 to 2005.
Overall, it is clear that the total amount of pollutants in the air decreased between these years. The decline in air pollutants from industrial sources was particularly significant.
In 1990, the total amount of air pollutants in the UK was 7 million tonnes. This figure fell sharply to 4 million tonnes in 1999, and then continued to decline to just over 3 million tonnes by the end of the period.
Industry accounted for 5.5 million tonnes of air pollutants in 1990. There was then a decrease throughout this period to a figure of 2 million tonnes by 2005, with a particularly sharp fall between 1993 and 1996. In contrast, the amount of air pollutants was much lower from transport and household sources. Air pollution from transport remained relatively constant at about 1 million tonnes from 1990 to 2005, whereas air pollutants from households saw a decrease from almost 1 million tonnes in 1990 to approximately 0.1 million tonnes by 2005.