condition mean min max ZT0-3 22.796833333333336 16.187 27.7056 ZT4-7 13.194849999999999 13.194849999999999 13.194849999999999 ZT8-11 16.0702 16.0702 16.0702 ZT12-15 22.79825 19.86405 25.73245 ZT16-19 24.1846 24.1846 24.1846 ZT20-23 31.74625 31.74625 31.74625