condition mean min max ZT0-3 7.141567499999999 6.21198 8.071155 ZT4-7 4.51414 4.51414 4.51414 ZT8-11 3.5158300000000002 3.5158300000000002 3.5158300000000002 ZT12-15 0 0 0 ZT16-19 5.305655 5.305655 5.305655 ZT20-23 6.8676449999999996 6.8676449999999996 6.8676449999999996