condition mean min max ZT0-3 0.1870435 0.1081235 0.3368155 ZT4-7 0.2424955 0.2424955 0.2424955 ZT8-11 0.0 0.0 0.0 ZT12-15 0.328742 0.1232025 0.5342815 ZT16-19 0.33883599999999997 0.33883599999999997 0.33883599999999997 ZT20-23 0.121602 0.121602 0.121602