condition mean min max ZT0-3 4.983455 4.983455 4.983455 ZT4-7 7.57849 7.57849 7.57849 ZT8-11 8.847755 8.847755 8.847755 ZT12-15 7.47015 7.47015 7.47015 ZT16-19 5.2305425 5.2305425 5.2305425 ZT20-23 4.80906 4.80906 4.80906