condition mean min max ZT0-3 844.5 844.5 844.5 ZT4-7 1360.6 1360.6 1360.6 ZT8-11 2238.75 2238.75 2238.75 ZT12-15 3523.95 3523.95 3523.95 ZT16-19 3156.55 3156.55 3156.55 ZT20-23 1479.05 1479.05 1479.05