condition mean min max ZT0-3 14.206736666666666 10.72471 18.34555 ZT4-7 16.97655 16.97655 16.97655 ZT8-11 9.3917 9.3917 9.3917 ZT12-15 12.676357499999998 8.567665 16.78505 ZT16-19 12.6809 12.6809 12.6809 ZT20-23 15.3768 15.3768 15.3768