condition mean min max ZT0-3 9.693989 9.693989 9.693989 ZT4-7 9.580859499999999 9.580859499999999 9.580859499999999 ZT8-11 9.201341 9.201341 9.201341 ZT12-15 9.7020055 9.7020055 9.7020055 ZT16-19 9.5460305 9.5460305 9.5460305 ZT20-23 9.24633 9.24633 9.24633