condition mean min max ZT0-3 271.680161 271.680161 271.680161 ZT4-7 478.2363125 478.2363125 478.2363125 ZT8-11 401.10639749999996 401.10639749999996 401.10639749999996 ZT12-15 732.017491 732.017491 732.017491 ZT16-19 394.342853 394.342853 394.342853 ZT20-23 452.73634100000004 452.73634100000004 452.73634100000004