condition mean min max ZT0-3 3.56569 1.282785 5.8485949999999995 ZT4-7 2.92374 2.92374 2.92374 ZT8-11 3.24919 3.24919 3.24919 ZT12-15 0 0 0 ZT16-19 3.512525 3.512525 3.512525 ZT20-23 3.533465 3.533465 3.533465