condition mean min max ZT0-3 4.2398975 3.8354500000000002 4.6443449999999995 ZT4-7 4.00863 4.00863 4.00863 ZT8-11 7.014345 7.014345 7.014345 ZT12-15 0 0 0 ZT16-19 7.32698 7.32698 7.32698 ZT20-23 6.46174 6.46174 6.46174