condition mean min max ZT0-3 68.121308 68.121308 68.121308 ZT4-7 258.9943945 258.9943945 258.9943945 ZT8-11 341.9698425 341.9698425 341.9698425 ZT12-15 297.49141099999997 297.49141099999997 297.49141099999997 ZT16-19 219.38077099999998 219.38077099999998 219.38077099999998 ZT20-23 166.9139295 166.9139295 166.9139295