condition mean min max ZT0-3 1.5827325 1.51872 1.6467450000000001 ZT4-7 1.844285 1.844285 1.844285 ZT8-11 0.9240745 0.9240745 0.9240745 ZT12-15 0 0 0 ZT16-19 1.597885 1.597885 1.597885 ZT20-23 2.19139 2.19139 2.19139