condition mean min max ZT0-3 11.4 11.4 11.4 ZT4-7 19.1 19.1 19.1 ZT8-11 16.15 16.15 16.15 ZT12-15 15.950000000000001 15.950000000000001 15.950000000000001 ZT16-19 10.7 10.7 10.7 ZT20-23 30.9 30.9 30.9