condition mean min max ZT0-3 247.9 247.9 247.9 ZT4-7 230.9 230.9 230.9 ZT8-11 220.7 220.7 220.7 ZT12-15 172.3 172.3 172.3 ZT16-19 218.60000000000002 218.60000000000002 218.60000000000002 ZT20-23 303.4 303.4 303.4