condition mean min max ZT0-3 0.23046063333333333 0.14761785 0.34349799999999997 ZT4-7 0.311338 0.311338 0.311338 ZT8-11 0.404471 0.404471 0.404471 ZT12-15 0.47075725 0.442845 0.4986695 ZT16-19 0.43994099999999997 0.43994099999999997 0.43994099999999997 ZT20-23 0.384847 0.384847 0.384847