condition mean min max ZT0-3 4.05469 4.05469 4.05469 ZT4-7 5.1921800000000005 5.1921800000000005 5.1921800000000005 ZT8-11 3.2477850000000004 3.2477850000000004 3.2477850000000004 ZT12-15 3.809895 3.809895 3.809895 ZT16-19 3.899485 3.899485 3.899485 ZT20-23 3.47419 3.47419 3.47419