condition mean min max ZT0-3 0.899628 0.899628 0.899628 ZT4-7 0.94816 0.94816 0.94816 ZT8-11 1.1167319999999998 1.1167319999999998 1.1167319999999998 ZT12-15 0.8482810000000001 0.8482810000000001 0.8482810000000001 ZT16-19 0.7832684999999999 0.7832684999999999 0.7832684999999999 ZT20-23 0.7979395 0.7979395 0.7979395