condition mean min max ZT0-3 1.1239075 1.1057549999999998 1.14206 ZT4-7 1.2962625 1.2962625 1.2962625 ZT8-11 1.23582 1.23582 1.23582 ZT12-15 0 0 0 ZT16-19 2.735445 2.735445 2.735445 ZT20-23 1.5667849999999999 1.5667849999999999 1.5667849999999999