condition mean min max ZT0-3 11.350000000000001 11.350000000000001 11.350000000000001 ZT4-7 5.1 5.1 5.1 ZT8-11 27.9 27.9 27.9 ZT12-15 14.899999999999999 14.899999999999999 14.899999999999999 ZT16-19 21.55 21.55 21.55 ZT20-23 29.0 29.0 29.0