Histograms of stellar-population parameters (thin line, derived using BC03 SSP models) of the 1480 quiescent galaxies with stellar mass 10.8 ≤ log₁₀ M_⋆ <  11.2 dex and at redshift 0.5 ≤ z <  0.7. From top to bottom, mass-weighted age, mass-weighted metallicity, and extinction (panels a, b, and c, respectively). The dashed line is the distribution fit, whereas the solid orange line is the parameter distributions after applying the MLE method to deconvolve uncertainty effects (further details in the text). The star-shaped marker and the solid black line illustrate the median and the 1σ width of the distributions, respectively. All the curves were normalised to the fitted number density (see Sect. 3 and Table 2).