condition mean min max ZT0-3 6.871404999999999 5.91852 7.8242899999999995 ZT4-7 12.80395 12.80395 12.80395 ZT8-11 10.758885 10.758885 10.758885 ZT12-15 0 0 0 ZT16-19 16.397750000000002 16.397750000000002 16.397750000000002 ZT20-23 11.6924 11.6924 11.6924