The data illustrate the average carbon dioxide emissions for each person in the UK, Sweden, and Portugal from 1967 to 2007.
Overall, it is noticeable that the highest levels of emissions were produced in the UK, while the lowest were in Portugal.
To elaborate, in 1967, Portugal was the cleanest country among the others, indicating lower than one metric tonne, but then rapidly jumped to 5 metric tonnes by 1997; until 2000, the results leveled out. In comparison, Italy commenced with more pollution, hitting just over 4 metric tonnes, then its emissions hurriedly leaped to about 6 metric tonnes in a decade. Thereafter, CO2 emissions saw a stable upward move, displaying approximately 8 metric tonnes, then until the end it was unchanged.
Sweden kicked off with around 8 metric tonnes, then between 1967 and 1987, results fluctuated, and then until 2007, the emissions significantly plunged to just below 6 metric tonnes of emissions. Lastly, the UK maintained the highest levels of emissions throughout the period, beginning with around 11 metric tonnes, but then saw a moderate decline of 3 metric tonnes by 2007.