condition mean min max ZT0-3 26.640115 26.640115 26.640115 ZT4-7 38.270829 38.270829 38.270829 ZT8-11 42.6633245 42.6633245 42.6633245 ZT12-15 37.8291055 37.8291055 37.8291055 ZT16-19 29.520825000000002 29.520825000000002 29.520825000000002 ZT20-23 28.315511 28.315511 28.315511