condition mean min max ZT0-3 3.9044729665 3.058083092 4.750862841 ZT4-7 7.31871252075 6.247660702000001 8.3897643395 ZT8-11 9.520161145500001 8.921388681 10.118933610000001 ZT12-15 11.8593882425 10.559308224999999 13.15946826 ZT16-19 12.299369505 11.78641802 12.81232099 ZT20-23 19.013728205 16.9955451 21.031911309999998