condition mean min max ZT0-3 0.5971561666666667 0.5178245 0.6561195 ZT4-7 0.146772 0.146772 0.146772 ZT8-11 0.3558865 0.3558865 0.3558865 ZT12-15 0.64035725 0.585339 0.6953754999999999 ZT16-19 0.7726284999999999 0.7726284999999999 0.7726284999999999 ZT20-23 1.2598115 1.2598115 1.2598115