The graph illustrates average carbon dioxide(CO2) emissions per person in the four different countries. Units are measured in metric tonnes.
Overall, at the beginning of the period, the amount of carbon emissions in the UK was higher than others, while level of CO2 in Portugal was the lowest among these countries. Moreover, the level of carbon emissions in Portugal and Italy experienced a significant rise, while during this period the amount of CO₂ in the UK and Sweden witnessed a slight decrease.
At the beginning of the period, the figure for the UK in 1967 stood at roughly 11 metric tonnes, which was the highest point, then fell slightly by 2007. Throughout the period, the amount of carbon emissions in Sweden reached a peak of around 11 metric tonnes in 1977, then declined sharply between 1977 and 1987 , before witnessed a slight decrease to about 5 metric tonnes by 2007, the same level as in Portugal.
In early 1967 the contribution of Italy was nearly 4 metric tonnes, then expex1rienced a significant rise, while the figure for Portugal increased considerably and it reached approximately 1 metric tonnes. The level of CO2 in Portugal was roughly 5 metric tonnes ,the same result as in Sweeden, in 2007, whereas the amount of carbon emissions in Italy reached 7 metric tonnes.