condition mean min max ZT0-3 42.300349999999995 41.65895 42.94175 ZT4-7 21.72 21.72 21.72 ZT8-11 15.03595 15.03595 15.03595 ZT12-15 0 0 0 ZT16-19 30.48345 30.48345 30.48345 ZT20-23 51.91175 51.91175 51.91175