Evolution of the gas disc masses (left), dust disc masses (middle), and dust-to-gas ratios (right) as a function of disc age using the α_v = 10⁻². Gas discs are formed with masses between 0.03 M_⊙ to 0.5 M_⊙. After 10 Myr of evolution about 1% of this initial mass remains. Dust disc masses are initially between 10 M_⊕ to 1000 M_⊕. The shortest lived dust discs are depleted in ~1 Myr, whilst the longest lived last up to 3–8 Myr, depending on if either the Pic2l or Kom2l photoevaporation prescription is used. Discs are formed from material with a dust-to-gas ratio of Z = 0.01, but, due to rapid loss of dust in the earliest phases of disc formation, the global dust-to-gas ratio of the discs is always below this value.