Regression analysis and calculating the coefficients in the uncertainty estimation formula for the MTGR with the metallicity-dependent coefficients. The slopes in graphs 6 and 12 were too small and ignored (see text). Two solutions were provided for c₉ and c₁₀: Regression line 1 is for the entire [M/H] range, and regression line 2 is a better estimate for −0.1 ≤ [M/H] ≤ 0.6. The zero points (ZPs) c₃, c₆, and c₁₀ were calculated by averaging the individual calculations, i.e., c₃ = (c₃[1]+c₃[2])/2, c₆ = (c₆[1]+c₆[2])/2, and c₁₀ = (c₁₀[1]+c₁₀[2]+c₁₀[3])/3.