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This graph demonstrates the mean carbon dioxide emitted per person in four countries, including UK, Sweden, Italy and Portugal, in the time period from 1967 to 2007. Units are measured in metric tones. Overall, British people released the most CO2, ranging from around 11 to nearly 9 tones in the mentioned period, while Portugal, by never emitting more than 6 tones, had the least emit. Although UK has emitted higher amounts of CO2 in comparison to other countries in total, it has experienced a decreasing rate. In Sweden, CO2 emittance rose from approximately 9 tones to more than 10 tone in the first ten years. However, in 1977 it declined and then decreased for the next 40 years and eventually reached less than 6 tone in 2007, which made Sweden one of the least CO2 producers. On the other hand, Italy and Portugal have increased their CO2 emittance constantly since 1967. Italy initiated from emitting just a bit more than 4 tones of CO2 in 1967 and increased it until 1997 and after that it remained steady for the last decade. Similarly, Portugal has followed the same manner and has grown CO2 formation from around 1 tones to five times, reaching the Sweden in 2007.