right, so it's one i want to, i didn't get time to do last week was to tell you where you specify that you want to perform a chow test, right, and the computer will generate both of  both of chow's tests with  one, the first one is where we've got enough observations in each sub sample, right, to estimate the regression, right, however, you may, you may detect and figure there is some structural change right at the end of your er sample of observations or alternatively right at the beginning.