condition mean min max ZT0-3 3.2293575 2.997995 3.46072 ZT4-7 5.638059999999999 5.638059999999999 5.638059999999999 ZT8-11 3.7489 3.7489 3.7489 ZT12-15 0 0 0 ZT16-19 6.189415 6.189415 6.189415 ZT20-23 5.480055 5.480055 5.480055