condition mean min max ZT0-3 0.6138216666666667 0.3997545 0.9251705 ZT4-7 0.2026335 0.2026335 0.2026335 ZT8-11 0.32984800000000003 0.32984800000000003 0.32984800000000003 ZT12-15 1.03608075 1.0075075 1.064654 ZT16-19 1.337755 1.337755 1.337755 ZT20-23 0.8036030000000001 0.8036030000000001 0.8036030000000001