condition mean min max ZT0-3 3.1366324999999997 3.0893699999999997 3.1838949999999997 ZT4-7 2.65045 2.65045 2.65045 ZT8-11 4.1333649999999995 4.1333649999999995 4.1333649999999995 ZT12-15 0 0 0 ZT16-19 4.124615 4.124615 4.124615 ZT20-23 3.3471200000000003 3.3471200000000003 3.3471200000000003