condition mean min max ZT0-3 9.017595 8.00824 10.02695 ZT4-7 8.187114999999999 8.187114999999999 8.187114999999999 ZT8-11 8.98677 8.98677 8.98677 ZT12-15 0 0 0 ZT16-19 11.3083 11.3083 11.3083 ZT20-23 11.536200000000001 11.536200000000001 11.536200000000001