condition mean min max ZT0-3 0.907214 0.907214 0.907214 ZT4-7 0.2603845 0.2603845 0.2603845 ZT8-11 1.3004099999999998 1.3004099999999998 1.3004099999999998 ZT12-15 9.42138 9.42138 9.42138 ZT16-19 2.70818 2.70818 2.70818 ZT20-23 1.57115 1.57115 1.57115