condition mean min max ZT0-3 7.5881 7.5881 7.5881 ZT4-7 5.353895 5.353895 5.353895 ZT8-11 9.596235 9.596235 9.596235 ZT12-15 8.39462 8.39462 8.39462 ZT16-19 7.534345 7.534345 7.534345 ZT20-23 5.4170549999999995 5.4170549999999995 5.4170549999999995