condition mean min max ZT0-3 1666.347441 1666.347441 1666.347441 ZT4-7 486.81584799999996 486.81584799999996 486.81584799999996 ZT8-11 522.0835845 522.0835845 522.0835845 ZT12-15 745.3538835 745.3538835 745.3538835 ZT16-19 1643.757034 1643.757034 1643.757034 ZT20-23 2509.10895 2509.10895 2509.10895