Trendline: Exactly What It Sounds Like

Make a trendline out of data. Simple as that.

I have some data (as sometimes happens) and I wanted a trend line. It’s not an absurd ask, but going to Google, the top result for the software I use is this bizarre set of instructions. It involves seemingly nonsensical steps (average valuess, plural?) and references UI elements that do not exist. I honestly have no idea when it was written, but long enough ago that the software used to support this pretty easily, I’d guess. 

This more recent conversation in the forums doesn’t inspire much hope either. These people are clearly experts, but even they seem stymied by this. They’re comfortable with a level of detail I’ve never even been exposed to with spreadsheets (a lot of the benefit of spreadsheets disappears the moment you get comfortable with programming). I just wanted a chart, and an idea of where the data is going. Is that such an unusual thing to ask that there is no immediately obvious way to do it?

There are charting tools out there that brag about trend lines but don’t seem to let me input my data. There are people out there with formulas (some of which are wrong, as it turns out). But I’ve got simple needs. Just show me a chart of my data. With a trend line. 

So I built it.