condition mean min max ZT0-3 31.259124 31.259124 31.259124 ZT4-7 32.2516735 32.2516735 32.2516735 ZT8-11 25.2438445 25.2438445 25.2438445 ZT12-15 21.2139405 21.2139405 21.2139405 ZT16-19 17.3236005 17.3236005 17.3236005 ZT20-23 17.4259195 17.4259195 17.4259195