condition mean min max ZT0-3 0.08651135 0.0584557 0.114567 ZT4-7 0.0383999 0.0383999 0.0383999 ZT8-11 0.0192662 0.0192662 0.0192662 ZT12-15 0 0 0 ZT16-19 0.0 0.0 0.0 ZT20-23 0.0191791 0.0191791 0.0191791