condition mean min max ZT0-3 91.663553 91.663553 91.663553 ZT4-7 175.334433 175.334433 175.334433 ZT8-11 269.685056 269.685056 269.685056 ZT12-15 203.164598 203.164598 203.164598 ZT16-19 128.6078885 128.6078885 128.6078885 ZT20-23 96.7332365 96.7332365 96.7332365