condition mean min max ZT0-3 9.990685 9.49592 10.48545 ZT4-7 7.3479399999999995 7.3479399999999995 7.3479399999999995 ZT8-11 7.232055 7.232055 7.232055 ZT12-15 0 0 0 ZT16-19 8.389610000000001 8.389610000000001 8.389610000000001 ZT20-23 9.321425 9.321425 9.321425