Magnetic field strength as a function of cooling age for metal-enriched H- and He-dominated white dwarfs from PEWDD. The black horizontal dashed line illustrates the threshold for detecting Zeeman splitting in flux spectra. The coloured horizontal dotted lines show the median values of magnetic field strength for H- (blue pentagons) and He- (orange hexagons) dominated atmospheres. The upper histogram shows the fraction of magnetic white dwarfs compared to the total number of metal-enriched white dwarfs in PEWDD. The right histogram illustrates the distribution of magnetic field strengths for H- and He-dominated white dwarfs. The points below the detection threshold are white dwarfs where no magnetic field has been detected, scattered to show the cooling age distribution compared to their magnetic counterparts.