(a): Example using AT 2020vdq to illustrate the calculation of the effective monitoring duration (EMD). Black triangles show the 5σ upper-limit of the CRTS data points, and the green line indicates the maximum L_V allowed by the observations as a function of t_peak. Observational time are converted to the phase before the ZTF TDE in the rest-frame. For a given L_V (example shown for L_V ∼ 10^43.14 erg/s, corresponding to M_V ∼ −19.4), the time ranges when the maximum allowed L_V is below this luminosity (red) are considered effectively monitored, while other times (blue) are not. (b): Resultant EMDs as functions of peak L_V for the sample. The dashed black line indicates the average EMD, and the red shaded region marks the typical L_peak range of SN Ia (−18 < M_V < −19.4).