condition mean min max ZT0-3 18.064975 17.4773 18.65265 ZT4-7 19.4122 19.4122 19.4122 ZT8-11 32.36705 32.36705 32.36705 ZT12-15 0 0 0 ZT16-19 37.39105 37.39105 37.39105 ZT20-23 30.863500000000002 30.863500000000002 30.863500000000002