Stellar mass-Sy2 fraction relation based on mid-infrared colour diagnostics (mIRdds) using central apertures. Environmental classifications follow Section 2.1. Stellar masses are binned as log (M_*/M_⊙), M1 ≤8.5, 8.5< M2 ≤9.0, 9.0< M3 ≤9.5, 9.5< M4 ≤10.0, 10.0< M5 ≤10.5, and 10.5< M6. Sy2 observed fractions for VCM, H I-deficient, and RPS galaxies are shown alongside median values from 100 stellar mass-matched bootstrap samples of field and H I-normal galaxies (see Section 4.2). Each panel includes galaxy counts, totals and fractions, and median stellar masses, for both bootstrap and original samples. WHAN-based Sy2 fractions from Cattorini et al. (2023) are overplotted for comparison. For original data and bootstrap medians, random uncertainties are expressed as the ratio of the square root of each Sy2 count to the total.