condition mean min max ZT0-3 4.578655 4.578655 4.578655 ZT4-7 4.92185 4.92185 4.92185 ZT8-11 4.0593200000000005 4.0593200000000005 4.0593200000000005 ZT12-15 3.55966 3.55966 3.55966 ZT16-19 3.798445 3.798445 3.798445 ZT20-23 4.3812549999999995 4.3812549999999995 4.3812549999999995