condition mean min max ZT0-3 4.083783759 1.039138636 7.128428882 ZT4-7 8.8189362705 7.858164609499999 9.779707931499999 ZT8-11 7.09113040575 6.215415479 7.9668453325 ZT12-15 2.52997052725 1.849411654 3.2105294005 ZT16-19 3.963913519 3.2047599150000003 4.723067123 ZT20-23 6.36825472525 5.927823621 6.8086858295