condition mean min max ZT0-3 262.561091 262.561091 262.561091 ZT4-7 296.552164 296.552164 296.552164 ZT8-11 284.320151 284.320151 284.320151 ZT12-15 323.18649 323.18649 323.18649 ZT16-19 298.60827600000005 298.60827600000005 298.60827600000005 ZT20-23 350.160754 350.160754 350.160754