condition mean min max ZT0-3 16.830271 16.830271 16.830271 ZT4-7 13.528104500000001 13.528104500000001 13.528104500000001 ZT8-11 14.8775935 14.8775935 14.8775935 ZT12-15 11.9766855 11.9766855 11.9766855 ZT16-19 15.024329999999999 15.024329999999999 15.024329999999999 ZT20-23 11.6613075 11.6613075 11.6613075