condition mean min max ZT0-3 2.3216200000000002 2.29284 2.3504 ZT4-7 1.63678 1.63678 1.63678 ZT8-11 1.1584675 1.1584675 1.1584675 ZT12-15 0 0 0 ZT16-19 2.17776 2.17776 2.17776 ZT20-23 2.083065 2.083065 2.083065