condition mean min max ZT0-3 15.5153 15.5153 15.5153 ZT4-7 13.2854 13.2854 13.2854 ZT8-11 10.764045 10.764045 10.764045 ZT12-15 11.65112 11.65112 11.65112 ZT16-19 15.25215 15.25215 15.25215 ZT20-23 14.576550000000001 14.576550000000001 14.576550000000001