The given line graph depicts average carbon dioxide (CO2) emission per person in the United Kingdom, Sweden, Italy and Portugal from 1967 to 2007.
Overall, it can be seen that the proportion of average carbon dioxide (CO2) emission in the United Kingdom and Sweden experienced a decline, while Italy and Portugal had increased over the period shown.
In 1967, the highest figure of average carbon dioxide (CO2) emission was the United Kingdom, at around 11 metric tonnes, while the least one was Portugual, at only around 1 metric tonnes. In addition, in the same year, the proportion of average carbon dioxide (CO2) emission in Sweden was higher than Italy, at around 8.5 metric tonnes and 4.2 metric tonnes, respectively. In 1977, the United Kingdom remained unchanged. In contrast, the figure in Sweden hit a peak at 10.2 metric tonnes in that year.
However, both the figure in the United Kingdom and Sweden continuously decreased until 2007, at 9 metric tonnes and 5.5 metric tonnes, respectively. Meanwhile, by 2007, the proportion of average carbon dioxide (CO2) emission in Italy and Portugual reached their highest point, at 7.8 metric tonnes in Italy and 5.5 metric tonnes in Portugual.
