condition mean min max ZT0-3 10.9 10.9 10.9 ZT4-7 6.0 6.0 6.0 ZT8-11 7.55 7.55 7.55 ZT12-15 13.15 13.15 13.15 ZT16-19 27.700000000000003 27.700000000000003 27.700000000000003 ZT20-23 40.25 40.25 40.25