condition mean min max ZT0-3 28.275509985 26.86238789 29.68863208 ZT4-7 15.468497915 13.498150975 17.438844855 ZT8-11 26.083947135000003 20.67556648 31.49232779 ZT12-15 41.152211972500005 39.47840639 42.82601755500001 ZT16-19 43.8158080475 43.306600995 44.3250151 ZT20-23 45.162319615 41.895627605 48.429011625