Total accretion rates onto white dwarfs with H- (blue hexagons) and He- (orange pentagons) dominated atmospheres as a function of temperature. The left panel shows total accretion rates extrapolated from that of Ṁ_Ca (or Ṁ_Si if Ca was not detected), assuming that the accreted material has bulk Earth abundance (McDonough 2000) with a Ca (Si) mass fraction of 1.71% (16%). The red rings and green diamonds highlight the systems where infrared excesses and gas emission have been detected respectively, implying the presence of a circumstellar disc. The right panel compares the extrapolated total accretion rate to the sum of the accretion rates of O, Mg, Si and Fe, which make up approximately 95% of the bulk Earth, represented by stars.