condition mean min max ZT0-3 9.65 9.65 9.65 ZT4-7 5.5 5.5 5.5 ZT8-11 23.950000000000003 23.950000000000003 23.950000000000003 ZT12-15 17.15 17.15 17.15 ZT16-19 28.15 28.15 28.15 ZT20-23 13.85 13.85 13.85