condition mean min max ZT0-3 76.634971 76.634971 76.634971 ZT4-7 69.9815535 69.9815535 69.9815535 ZT8-11 63.3394675 63.3394675 63.3394675 ZT12-15 74.77241699999999 74.77241699999999 74.77241699999999 ZT16-19 81.4468935 81.4468935 81.4468935 ZT20-23 80.95285150000001 80.95285150000001 80.95285150000001