Changes in slope

[jpen]

Hello,

I have data in row 4 of a Excel sheet. Data starts at column F. Every month a datapoint is added to the dataset. I'am calculating the slope of the dataset. But what I want is to see what the change of slope.

Example
1, 3, 3, 2, 4, 5 gives a slope of 0.63
by adding a new data point the data set looks
1, 3, 3, 2, 4, 5, 1 gives a slope of 0.18

Now I want to now the change in slope so 0.63-0.18 = 0.45

Problem is how to get the column position as a variable.

I prefer a solution as a function on a worksheet if that is to hard then VBA code will be great.

Any ideas ?

 

[GlennUK]

How are you calculating the slope? Aren't you getting the column position of the end of the data for that?

 

[jamielill]

Are you using the built in slope formula?

 

[jpen]

I calculate the slope using the standard slope function of Excel.

I have found the solution us dynamic range.