condition mean min max ZT0-3 4.16137 2.424135 5.6089 ZT4-7 1.801265 1.801265 1.801265 ZT8-11 3.11845 3.11845 3.11845 ZT12-15 5.92931 5.623545 6.235075 ZT16-19 6.408505 6.408505 6.408505 ZT20-23 6.108275 6.108275 6.108275