condition mean min max ZT0-3 15.085575 12.2638 17.90735 ZT4-7 15.835799999999999 15.835799999999999 15.835799999999999 ZT8-11 33.51 33.51 33.51 ZT12-15 0 0 0 ZT16-19 41.814350000000005 41.814350000000005 41.814350000000005 ZT20-23 27.0748 27.0748 27.0748