condition mean min max ZT0-3 9.090412 9.090412 9.090412 ZT4-7 8.726234999999999 8.726234999999999 8.726234999999999 ZT8-11 8.006935499999999 8.006935499999999 8.006935499999999 ZT12-15 12.504446999999999 12.504446999999999 12.504446999999999 ZT16-19 8.921458000000001 8.921458000000001 8.921458000000001 ZT20-23 10.199223 10.199223 10.199223