condition mean min max ZT0-3 10.363239793999998 8.850249293 11.876230295 ZT4-7 18.06390879 16.633081869999998 19.49473571 ZT8-11 16.628321005 16.304538265 16.952103745 ZT12-15 40.007363745000006 32.316239785 47.698487705000005 ZT16-19 52.9116165275 50.029634985 55.79359807 ZT20-23 71.14726464750001 69.784751105 72.50977819