condition mean min max ZT0-3 12.84281904925 11.7921415785 13.89349652 ZT4-7 9.83866415875 8.8126617975 10.86466652 ZT8-11 15.089683115 12.283980455 17.895385775 ZT12-15 22.3898325475 19.245118825 25.53454627 ZT16-19 44.304794602499996 35.870143205 52.739446 ZT20-23 115.08042962000002 93.68202214 136.47883710000002