condition mean min max ZT0-3 3.22181 2.98369 3.45993 ZT4-7 3.57151 3.57151 3.57151 ZT8-11 4.2824100000000005 4.2824100000000005 4.2824100000000005 ZT12-15 0 0 0 ZT16-19 5.4133949999999995 5.4133949999999995 5.4133949999999995 ZT20-23 4.053545 4.053545 4.053545