Abundance patterns are displayed as box and whisker plots for a) the normal stars and b) the CP stars. Boxes correspond to the 16th and 84th percentiles of the abundance distribution for each element, thick horizontal lines represent the median value, and the whiskers span from the minimum to the maximum values. The width of the boxes is proportional to the square root of the number of values. The horizontal dashed line stands for the solar values. In the top panel, median values and 16th and 84th percentiles derived from the comparison stars are plotted on the right side of the boxes, as filled squares and thick vertical lines. The number of abundance determinations is indicated when five or more abundances are available, and all individual determinations are displayed when the number is less than five (see Sect. 8.1).