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Statistical data set

Figure 8: Annual mean hours per site when PM10 pollution was 鈥楳oderate鈥� or higher, for urban background sites, 1992 to 2024

Updated 26 June 2025

锘縎ite type Year Daily Air Quality Index Mean number of hours per site Number of sites
Urban Background 1992 Moderate 4 400.50 2
Urban Background 1993 Moderate 4 403.40 5
Urban Background 1994 Moderate 4 367.3076923 13
Urban Background 1995 Moderate 4 342.3076923 13
Urban Background 1996 Moderate 4 348.13 16
Urban Background 1997 Moderate 4 309.50 26
Urban Background 1998 Moderate 4 189.7272727 33
Urban Background 1999 Moderate 4 125.1818182 33
Urban Background 2000 Moderate 4 101.8235294 34
Urban Background 2001 Moderate 4 120.8139535 43
Urban Background 2002 Moderate 4 90.53846154 39
Urban Background 2003 Moderate 4 227.4473684 38
Urban Background 2004 Moderate 4 73.10 39
Urban Background 2005 Moderate 4 72.11111111 36
Urban Background 2006 Moderate 4 119.3589744 39
Urban Background 2007 Moderate 4 102.38 32
Urban Background 2008 Moderate 4 75.67857143 28
Urban Background 2009 Moderate 4 64.28571429 21
Urban Background 2010 Moderate 4 64.73684211 19
Urban Background 2011 Moderate 4 115.1666667 24
Urban Background 2012 Moderate 4 73.56 25
Urban Background 2013 Moderate 4 51.45 20
Urban Background 2014 Moderate 4 55.82608696 23
Urban Background 2015 Moderate 4 53.7826087 23
Urban Background 2016 Moderate 4 35.09090909 22
Urban Background 2017 Moderate 4 41.33333333 24
Urban Background 2018 Moderate 4 17.45454545 22
Urban Background 2019 Moderate 4 68.46153846 26
Urban Background 2020 Moderate 4 13.03 40
Urban Background 2021 Moderate 4 10.89473684 38
Urban Background 2022 Moderate 4 35.04545455 44
Urban Background 2023 Moderate 4 8.79 53
Urban Background 2024 Moderate 4 6.684210526 57
Urban Background 1992 Moderate 5 202.50 2
Urban Background 1993 Moderate 5 306.00 5
Urban Background 1994 Moderate 5 224.4615385 13
Urban Background 1995 Moderate 5 222.6923077 13
Urban Background 1996 Moderate 5 229.31 16
Urban Background 1997 Moderate 5 150.3846154 26
Urban Background 1998 Moderate 5 84.96969697 33
Urban Background 1999 Moderate 5 45.12121212 33
Urban Background 2000 Moderate 5 40.76470588 34
Urban Background 2001 Moderate 5 54.44186047 43
Urban Background 2002 Moderate 5 42.82051282 39
Urban Background 2003 Moderate 5 127.5789474 38
Urban Background 2004 Moderate 5 21.48717949 39
Urban Background 2005 Moderate 5 25.19444444 36
Urban Background 2006 Moderate 5 51.56410256 39
Urban Background 2007 Moderate 5 57.06 32
Urban Background 2008 Moderate 5 40.00 28
Urban Background 2009 Moderate 5 36.47619048 21
Urban Background 2010 Moderate 5 17.31578947 19
Urban Background 2011 Moderate 5 63.38 24
Urban Background 2012 Moderate 5 45.96 25
Urban Background 2013 Moderate 5 27.05 20
Urban Background 2014 Moderate 5 24.13043478 23
Urban Background 2015 Moderate 5 26.30434783 23
Urban Background 2016 Moderate 5 20.45454545 22
Urban Background 2017 Moderate 5 16.29166667 24
Urban Background 2018 Moderate 5 10.13636364 22
Urban Background 2019 Moderate 5 28.57692308 26
Urban Background 2020 Moderate 5 7.28 40
Urban Background 2021 Moderate 5 3.763157895 38
Urban Background 2022 Moderate 5 14.63636364 44
Urban Background 2023 Moderate 5 2.509433962 53
Urban Background 2024 Moderate 5 2.719298246 57
Urban Background 1992 Moderate 6 132.00 2
Urban Background 1993 Moderate 6 250.60 5
Urban Background 1994 Moderate 6 164.8461538 13
Urban Background 1995 Moderate 6 164.7692308 13
Urban Background 1996 Moderate 6 161.00 16
Urban Background 1997 Moderate 6 92.07692308 26
Urban Background 1998 Moderate 6 52.60606061 33
Urban Background 1999 Moderate 6 19.27272727 33
Urban Background 2000 Moderate 6 17.64705882 34
Urban Background 2001 Moderate 6 29.40 43
Urban Background 2002 Moderate 6 16.41025641 39
Urban Background 2003 Moderate 6 70.36842105 38
Urban Background 2004 Moderate 6 6.384615385 39
Urban Background 2005 Moderate 6 12.69444444 36
Urban Background 2006 Moderate 6 25.33333333 39
Urban Background 2007 Moderate 6 40.59 32
Urban Background 2008 Moderate 6 27.21428571 28
Urban Background 2009 Moderate 6 15.0952381 21
Urban Background 2010 Moderate 6 9.947368421 19
Urban Background 2011 Moderate 6 37.75 24
Urban Background 2012 Moderate 6 20.48 25
Urban Background 2013 Moderate 6 18.70 20
Urban Background 2014 Moderate 6 14.82608696 23
Urban Background 2015 Moderate 6 7.47826087 23
Urban Background 2016 Moderate 6 12.04545455 22
Urban Background 2017 Moderate 6 6.916666667 24
Urban Background 2018 Moderate 6 5.454545455 22
Urban Background 2019 Moderate 6 13.88461538 26
Urban Background 2020 Moderate 6 3.80 40
Urban Background 2021 Moderate 6 0.447368421 38
Urban Background 2022 Moderate 6 9.840909091 44
Urban Background 2023 Moderate 6 0.754716981 53
Urban Background 2024 Moderate 6 1.210526316 57
Urban Background 1992 High 7 95.00 2
Urban Background 1993 High 7 119.40 5
Urban Background 1994 High 7 80.69 13
Urban Background 1995 High 7 66.00 13
Urban Background 1996 High 7 90.19 16
Urban Background 1997 High 7 52.88461538 26
Urban Background 1998 High 7 23.72727273 33
Urban Background 1999 High 7 6.666666667 33
Urban Background 2000 High 7 8.882352941 34
Urban Background 2001 High 7 13.27906977 43
Urban Background 2002 High 7 4.333333333 39
Urban Background 2003 High 7 21.86842105 38
Urban Background 2004 High 7 2.717948718 39
Urban Background 2005 High 7 5.722222222 36
Urban Background 2006 High 7 9.36 39
Urban Background 2007 High 7 23.25 32
Urban Background 2008 High 7 13.10714286 28
Urban Background 2009 High 7 6.047619048 21
Urban Background 2010 High 7 4.263157895 19
Urban Background 2011 High 7 16.20833333 24
Urban Background 2012 High 7 6.60 25
Urban Background 2013 High 7 3.45 20
Urban Background 2014 High 7 8.130434783 23
Urban Background 2015 High 7 1.00 23
Urban Background 2016 High 7 4.363636364 22
Urban Background 2017 High 7 0.791666667 24
Urban Background 2018 High 7 1.181818182 22
Urban Background 2019 High 7 1.384615385 26
Urban Background 2020 High 7 1.98 40
Urban Background 2021 High 7 0.00 38
Urban Background 2022 High 7 3.295454545 44
Urban Background 2023 High 7 0.547169811 53
Urban Background 2024 High 7 0.438596491 57
Urban Background 1992 High 8 98.50 2
Urban Background 1993 High 8 83.20 5
Urban Background 1994 High 8 51.23076923 13
Urban Background 1995 High 8 42.61538462 13
Urban Background 1996 High 8 63.38 16
Urban Background 1997 High 8 30.96153846 26
Urban Background 1998 High 8 11.60606061 33
Urban Background 1999 High 8 3.242424242 33
Urban Background 2000 High 8 3.647058824 34
Urban Background 2001 High 8 8.465116279 43
Urban Background 2002 High 8 1.974358974 39
Urban Background 2003 High 8 5.842105263 38
Urban Background 2004 High 8 2.076923077 39
Urban Background 2005 High 8 2.222222222 36
Urban Background 2006 High 8 6.128205128 39
Urban Background 2007 High 8 11.66 32
Urban Background 2008 High 8 6.535714286 28
Urban Background 2009 High 8 3.285714286 21
Urban Background 2010 High 8 1.526315789 19
Urban Background 2011 High 8 8.00 24
Urban Background 2012 High 8 2.36 25
Urban Background 2013 High 8 0.95 20
Urban Background 2014 High 8 1.434782609 23
Urban Background 2015 High 8 0.39 23
Urban Background 2016 High 8 0.409090909 22
Urban Background 2017 High 8 0.38 24
Urban Background 2018 High 8 1.090909091 22
Urban Background 2019 High 8 0.50 26
Urban Background 2020 High 8 0.30 40
Urban Background 2021 High 8 0.00 38
Urban Background 2022 High 8 1.522727273 44
Urban Background 2023 High 8 0.132075472 53
Urban Background 2024 High 8 0.00 57
Urban Background 1992 High 9 46.00 2
Urban Background 1993 High 9 66.80 5
Urban Background 1994 High 9 33.69230769 13
Urban Background 1995 High 9 20.07692308 13
Urban Background 1996 High 9 48.31 16
Urban Background 1997 High 9 19.11538462 26
Urban Background 1998 High 9 7.03 33
Urban Background 1999 High 9 1.03030303 33
Urban Background 2000 High 9 2.470588235 34
Urban Background 2001 High 9 5.441860465 43
Urban Background 2002 High 9 1.846153846 39
Urban Background 2003 High 9 3.578947368 38
Urban Background 2004 High 9 0.58974359 39
Urban Background 2005 High 9 2.083333333 36
Urban Background 2006 High 9 4.615384615 39
Urban Background 2007 High 9 8.44 32
Urban Background 2008 High 9 3.892857143 28
Urban Background 2009 High 9 0.619047619 21
Urban Background 2010 High 9 0.894736842 19
Urban Background 2011 High 9 3.791666667 24
Urban Background 2012 High 9 1.44 25
Urban Background 2013 High 9 0.00 20
Urban Background 2014 High 9 0.304347826 23
Urban Background 2015 High 9 0.00 23
Urban Background 2016 High 9 0.227272727 22
Urban Background 2017 High 9 0.75 24
Urban Background 2018 High 9 0.227272727 22
Urban Background 2019 High 9 0.730769231 26
Urban Background 2020 High 9 0.53 40
Urban Background 2021 High 9 0.00 38
Urban Background 2022 High 9 0.25 44
Urban Background 2023 High 9 0.04 53
Urban Background 2024 High 9 0.00 57
Urban Background 1992 Very High 10 171.00 2
Urban Background 1993 Very High 10 69.40 5
Urban Background 1994 Very High 10 48.15384615 13
Urban Background 1995 Very High 10 26.46153846 13
Urban Background 1996 Very High 10 79.63 16
Urban Background 1997 Very High 10 26.11538462 26
Urban Background 1998 Very High 10 9.363636364 33
Urban Background 1999 Very High 10 2.666666667 33
Urban Background 2000 Very High 10 3.705882353 34
Urban Background 2001 Very High 10 12.6744186 43
Urban Background 2002 Very High 10 3.846153846 39
Urban Background 2003 Very High 10 4.736842105 38
Urban Background 2004 Very High 10 2.256410256 39
Urban Background 2005 Very High 10 5.00 36
Urban Background 2006 Very High 10 5.769230769 39
Urban Background 2007 Very High 10 10.19 32
Urban Background 2008 Very High 10 4.785714286 28
Urban Background 2009 Very High 10 0.00 21
Urban Background 2010 Very High 10 1.894736842 19
Urban Background 2011 Very High 10 5.166666667 24
Urban Background 2012 Very High 10 0.00 25
Urban Background 2013 Very High 10 0.00 20
Urban Background 2014 Very High 10 3.30 23
Urban Background 2015 Very High 10 0.00 23
Urban Background 2016 Very High 10 2.272727273 22
Urban Background 2017 Very High 10 0.916666667 24
Urban Background 2018 Very High 10 0.00 22
Urban Background 2019 Very High 10 1.230769231 26
Urban Background 2020 Very High 10 0.83 40
Urban Background 2021 Very High 10 0.00 38
Urban Background 2022 Very High 10 0.00 44
Urban Background 2023 Very High 10 0.320754717 53
Urban Background 2024 Very High 10 0.00 57