condition mean min max ZT0-3 4.69115 4.44049 4.94181 ZT4-7 6.0965 6.0965 6.0965 ZT8-11 6.7118649999999995 6.7118649999999995 6.7118649999999995 ZT12-15 0 0 0 ZT16-19 5.993905 5.993905 5.993905 ZT20-23 6.17248 6.17248 6.17248