The graph is based on the 90.41 percentile of PM10 daily mean concentration values corresponding to the 36th highest daily mean for each Member State; the boxes present the range of concentrations at all stations types (in μg/m3) officially reported by the EU Member States and how the concentrations relate to the limit value set by EU legislation (marked by the red line). The diagram indicates the lowest and highest observations, the means and the lower and upper quartiles. The lower quartile splits the lowest 25 % of the data and the upper quartile splits the highest 25 % of the data. The graph is based on PM2.5 annual mean concentration values; they present the range of concentrations at all stations types (in μg/m3) officially reported by the EU Member States and how the concentrations relate to the target value set by EU legislation (marked by the red line). The diagram indicates the lowest and highest observations, the means and the lower and upper quartiles. The lower quartile splits the lowest 25 % of the data and the upper quartile splits the highest 25 % of the data. The graph is based on the 93.15 percentile of maximum daily 8-hour mean concentration values corresponding to the 26th highest daily maximum of the running 8-h mean for each Member State; the boxes present the range of concentrations at all stations types (in μg/m3) officially reported by the EU Member States and how the concentrations relate to the target value set by EU legislation (marked by the red line). The diagram indicates the lowest and highest observations, the means and the lower and upper quartiles. The lower quartile splits the lowest 25 % of the data and the upper quartile splits the highest 25 % of the data.