condition mean min max ZT0-3 5.24496 2.93275 6.56438 ZT4-7 3.71551 3.71551 3.71551 ZT8-11 4.226535 4.226535 4.226535 ZT12-15 5.6470875 5.32153 5.972645 ZT16-19 6.636934999999999 6.636934999999999 6.636934999999999 ZT20-23 9.438095 9.438095 9.438095