condition mean min max ZT0-3 4.752513442 4.49513796 5.009888924 ZT4-7 5.288593338249999 4.1017282635 6.475458412999999 ZT8-11 7.9262546705000005 7.050411129 8.802098212 ZT12-15 8.6236326095 8.2602363945 8.9870288245 ZT16-19 7.8250555102499995 6.428288438 9.2218225825 ZT20-23 16.066805602499997 13.410616319999999 18.722994885