condition mean min max ZT0-3 15.2945 15.2945 15.2945 ZT4-7 16.6939 16.6939 16.6939 ZT8-11 9.660895 9.660895 9.660895 ZT12-15 8.78293 8.78293 8.78293 ZT16-19 13.8309 13.8309 13.8309 ZT20-23 12.6587 12.6587 12.6587