condition mean min max ZT0-3 2.6912825000000002 2.6020450000000004 2.78052 ZT4-7 2.14376 2.14376 2.14376 ZT8-11 2.946635 2.946635 2.946635 ZT12-15 0 0 0 ZT16-19 3.228045 3.228045 3.228045 ZT20-23 5.591145 5.591145 5.591145