condition mean min max ZT0-3 30.75 30.75 30.75 ZT4-7 8.3 8.3 8.3 ZT8-11 9.2 9.2 9.2 ZT12-15 6.2 6.2 6.2 ZT16-19 15.8 15.8 15.8 ZT20-23 13.100000000000001 13.100000000000001 13.100000000000001