condition mean min max ZT0-3 2.515645 1.65558 3.3757099999999998 ZT4-7 1.4316749999999998 1.4316749999999998 1.4316749999999998 ZT8-11 2.21679 2.21679 2.21679 ZT12-15 0 0 0 ZT16-19 3.47445 3.47445 3.47445 ZT20-23 3.2702600000000004 3.2702600000000004 3.2702600000000004