Percentage of population resident in urban areas potentially exposed to NO2 concentration levels exceeding the annual limit value, EEA member countries, 1997-2006
Data prior to 1996 with a coverage of less than 50 million people are not representative for the European situation. Year-to-year variations in exposure classes (e.g. % of urban population in the class 0-26 µg/m3) are partly caused by changes in spatial coverage. Only urban background stations have been included in the calculations.