Key points:
1. Ensure that the numeric format of the equation legend is set to
Scientific with 15 significant digits

2. Break up calculation of the value into several cells, depending on
the number of key parts of the equation; for example, order level in
polynomial equations.

3. The value of "y" in the equation is not based upon the actual value
of "x". It is based upon the relative number of data points for "x".
You will lose your mind trying to apply the equation to the actual
value of "x".

4. When applying the equation to a different set of data points,
create a new source value of "x" based upon the number of the data
points from which the equation was derived. For example, if the
number of source data points is 66, and the number of new data point
is 81, then the value of each of the new data points is the number of
the data point multiplied by 66/81.