Number of ions per spectrum c_X, where X denotes the species observed on mass 52 u/e (i.e., CH₃ ³⁷ Cl, NCCN, and C₄H₄). The underlying data were collected in the four days between 13 and 16 March 2016, including the day of the outbound equinox on 16 March 2016. Counting symbols on the x-axis mark times of analyzed spectra. HCN data has been evaluated in an automated data evaluation pipeline and time-interpolated as described in Rubin et al. (2019). Error bars indicate statistical errors.