condition mean min max ZT0-3 18.5532 13.11485 23.99155 ZT4-7 20.3001 20.3001 20.3001 ZT8-11 12.9046 12.9046 12.9046 ZT12-15 0 0 0 ZT16-19 38.7084 38.7084 38.7084 ZT20-23 49.6298 49.6298 49.6298