condition mean min max ZT0-3 24.5408171375 19.005746875 30.075887400000003 ZT4-7 19.4559349725 15.393516495 23.51835345 ZT8-11 20.77388178 20.722520215000003 20.825243344999997 ZT12-15 11.257495439500001 8.858825913 13.656164966 ZT16-19 7.7484843547499995 7.5411959175 7.955772791999999 ZT20-23 8.635152177250001 8.1756401445 9.094664210000001