condition mean min max ZT0-3 3.8499999999999996 3.8499999999999996 3.8499999999999996 ZT4-7 19.5 19.5 19.5 ZT8-11 9.95 9.95 9.95 ZT12-15 17.1 17.1 17.1 ZT16-19 12.7 12.7 12.7 ZT20-23 3.4 3.4 3.4