o Loans made and intended to be sold by the originating lender or creditor to FNMA, GNMA, or FHLMC (or its successor); 7 or o Loans that are the subject of a home equity conversion mortgage or reverse mortgage issued by a lender or creditor subject to the regulation. 4
1 Draw the max line -- the one with as large a slope as you think reasonable (taking into account error bars), while still doing a fair job of representing all the data. Measure the slope of this line.  Calculate the uncertainty in the slope as one-half of the difference between max and min slopes.
The next variable is the Standard Error of Difference in Means and to calculate it we take the square root of the pooled sample variance times the sum of one over the counts for the winter and summer data points (i.e. 1/30 + 1/30).