Calculation of the geographical centre of the residents' real estates within each 1 × 1 kilometre grid cell. Small grid cells: grid cells for modelled annual mean of NO2 (250 × 250 m). Large bold grid cell: 1 km2. Small black dots: the centre coordinates of the real estate (according to the National Registry) for each individual in population data set PD1. Black centre cross: the generalised position of the individual's real estate, within the specific km2, according to population data set PD2. White crossed circle: calculated geographical centre of the residents' real estate within the specific km2. White-edged grid cells: the cells within the concentration grid which, through bilinear interpolation were used to assign an NO2 exposure value to the individuals in the repositioned PD2.