condition mean min max ZT0-3 87.078362 87.078362 87.078362 ZT4-7 55.947488500000006 55.947488500000006 55.947488500000006 ZT8-11 49.732725 49.732725 49.732725 ZT12-15 48.948088999999996 48.948088999999996 48.948088999999996 ZT16-19 27.133166499999998 27.133166499999998 27.133166499999998 ZT20-23 36.2656535 36.2656535 36.2656535