condition mean min max ZT0-3 42.355413415 33.32902483 51.381802 ZT4-7 19.1381423575 17.77648619 20.499798525 ZT8-11 21.176355425 19.05839811 23.294312740000002 ZT12-15 16.58083592 15.716223555 17.445448285 ZT16-19 17.599934507500002 15.58007225 19.619796765 ZT20-23 24.2706578075 23.34292354 25.198392075