condition mean min max ZT0-3 9.75 9.75 9.75 ZT4-7 8.5 8.5 8.5 ZT8-11 8.75 8.75 8.75 ZT12-15 16.2 16.2 16.2 ZT16-19 14.5 14.5 14.5 ZT20-23 11.100000000000001 11.100000000000001 11.100000000000001