condition mean min max ZT0-3 5.642961666666666 3.13137 9.72396 ZT4-7 4.333715 4.333715 4.333715 ZT8-11 6.99338 6.99338 6.99338 ZT12-15 11.8188025 7.900055 15.73755 ZT16-19 8.867745 8.867745 8.867745 ZT20-23 7.501365 7.501365 7.501365