condition mean min max ZT0-3 21.5 21.5 21.5 ZT4-7 8.1 8.1 8.1 ZT8-11 19.6 19.6 19.6 ZT12-15 13.85 13.85 13.85 ZT16-19 11.6 11.6 11.6 ZT20-23 15.049999999999999 15.049999999999999 15.049999999999999