Evolution of the logarithmic production rates ratios of each species with respect to OH and to CN as a function of heliocentric distance. The dashed red line represents the mean value of typical comets as defined in A’Hearn et al. (1995), while the blue line represents the mean value of the depleted group. Bottom panels: dust-to-gas ratio represented by A(0)fρ-to-OH and A(0)fρ-to-CN. The vertical dashed line shows the perihelion distance on September 10, 2018, at r_h = 1.01 au.