condition mean min max ZT0-3 9.3957075 7.886285000000001 10.90513 ZT4-7 12.316600000000001 12.316600000000001 12.316600000000001 ZT8-11 13.305700000000002 13.305700000000002 13.305700000000002 ZT12-15 0 0 0 ZT16-19 27.253249999999998 27.253249999999998 27.253249999999998 ZT20-23 21.3467 21.3467 21.3467