Display Year to Date Percent Change

The Problem

I find this code has a fatal flaw. The error message makes the point pretty clear. The fromDate variable must be before (less than) the toDate. The problem occurs because for every bar on the chart this code is being evaluated. When the code assigns yearstart it does so for each bar on the chart. I keep saying chart and this is a watchlist. But it helps if you understand this from the perspective of the chart.

So for each bar available to the watchlist the code assigns yearstart = GetYear() * 10000 + 101. Which the author obviously intended to compute as: 2018 * 10000 + 101 which equals 20,180,101. That would be Jan 1st of 2018. But you have bars being evaluated that are from the year 2017. So each bar’s date is going to impact this assigned value of the yearstart variable.

Did you get that?

Do you see the problem here? The code is written expecting the yearstart to be a static value, the same for every bar being evaluated. This would only be the case on an intraday time frame the historical data available to a custom watchlist is less than 1 year.

But it’s worse than that

And despite what the comments say at the top of this code. GetYYYYMMDD() does not return today’s date. It returns the date of the current bar.

If you followed all of that you see that the error is actually stating: “The fromDate cannot be the same as the toDate”. Because they it is written these two variables are always equal. They are the same thing.

The Code

Ok, enough with all that. The code never worked in the first place. The author should have known this and never published it. But that is water under the bridge. Here is a much more elegant and reliable way to achieve the stated goal. Screenshot included below showing the result.

This MUST be set to a daily time frame. It will NOT work on any intraday time frame.

def startOfYear = GetYear() <> GetYear()[1];
rec startingClose = if startOfYear then close[1] else startingClose[1];
plot percentChange = 100 * (close / startingClose - 1);
percentChange.AssignValueColor(if percentChange > 1.0 then Color.BLACK else if percentChange < -1.0 then Color.BLACK else Color.CURRENT); AssignBackgroundColor(if percentChange > 1.0 then Color.GREEN else if percentChange < -1.0 then Color.RED else Color.CURRENT);