Traders' Tips by Technical Analysis, Inc.
MICROSOFT EXCEL 3.0
Here's a method to calculate and plot a trendline from the data in a spreadsheet. A trendline is a straight
line that is a plot of rise over run. The run calculation is easy to do because the run is equidistant between
the values on the X-axis (time). Finding the rise requires identifying the difference between the two
highest points (for a downward trendline) or the two lowest points (for an uptrend). Excel can locate
these values. Our example will be for a downward trendline (Figure 1). The first step is to plot the data
(such as a close-only chart) so you can estimate where the high or low values may be. In our example,
using the closing price of the Dow Jones Transportation Average (DJTA), the high closing value appears
to be near early June. In my spreadsheet, this is in the range of cells B35 to B53. Return to the
spreadsheet and use the following formula for returning the highest value from a range of cells.