condition mean min max ZT0-3 8.35 8.35 8.35 ZT4-7 3.3 3.3 3.3 ZT8-11 8.95 8.95 8.95 ZT12-15 7.05 7.05 7.05 ZT16-19 15.350000000000001 15.350000000000001 15.350000000000001 ZT20-23 14.55 14.55 14.55