condition mean min max ZT0-3 12.08475 11.995650000000001 12.17385 ZT4-7 9.441875 9.441875 9.441875 ZT8-11 9.703075 9.703075 9.703075 ZT12-15 0 0 0 ZT16-19 15.107099999999999 15.107099999999999 15.107099999999999 ZT20-23 12.01615 12.01615 12.01615