One can overlay two charts for this and course they will switch back and forth, but is there an indicator which would show this? Suggestions appreciated.
Leading and lagging, versus co-related, are two very different things. https://tylervigen.com/spurious-correlations Posit a theoretical connection, first, and then seek to disprove it. It won't *guarantee* that you're posited connection is sound, but it'll sure cut down on noise. FWIW, there is no *direct* "T/A" tool for testing such a hypothesis, but one this you might do is create a single inter-market ("spread") product, and see how it trades over time. Do that logarithmically, and you'll have percent changes that don't depend so much on units.
If you have ThinkorSwim you can use this custom study that will normalize and compare 10 different instruments. It's called the "Multiple Instruments Comparison" study. It's free. https://github.com/jshingler/TOS-and-Thinkscript-Snippet-Collection/blob/master/TOS & Thinkscript Collection.pdf It's good for comparing highly correlated instruments. You can check your read on the market against a basket. Here's a screen of me using a modified version of it.
Correlation is the wrong metric to be looking at in the first place. Cointegration is the proper metric. Now down that rabbit hole you go.
%% Yes; more than one way to do that.Gain year to date is one of the better ways..................................................................................................................