condition mean min max ZT0-3 9.5960416195 9.477723171000001 9.714360068 ZT4-7 14.890110155 12.086103895 17.694116415 ZT8-11 21.3591904875 19.213908879999998 23.504472095 ZT12-15 17.6932508525 15.635914360000001 19.750587345 ZT16-19 21.72125709 18.021485745 25.421028435 ZT20-23 28.873647472499997 26.96898422 30.778310724999997