Example of SFH and MEH for a galaxy with LEGA-C ID: M23 – 151373. Left panel: Mass-weights map of the best-fitting spectrum. The white dots in the map correspond to the combination of age and metallicity of each template used for the fits. The color bar represents the mass weights assigned to SSPs in the best-fitting spectrum. Middle panel: SFH (solid green line) of the fitted galaxy, calculated as the cumulative sum of the rebinned mass weights, as a function of the cosmic formation time. Right panel: MEH (solid red line) of the fitted galaxy, calculated using Equation (5), as a function of the cosmic formation time. In the middle and right panels, the dashed and dotted lines respectively indicate τ₇₅ and τ₉₀, namely the formation time at which the galaxy has reached 75% and 90% of its mass.