condition mean min max ZT0-3 20.700000000000003 20.700000000000003 20.700000000000003 ZT4-7 19.3 19.3 19.3 ZT8-11 8.4 8.4 8.4 ZT12-15 19.4 19.4 19.4 ZT16-19 28.55 28.55 28.55 ZT20-23 40.4 40.4 40.4