Under settings, click "show difference" to see the difference between the two averages. This can also be called positive/negative drift. Switch to weekly/monthly S&P 500 to witness positive drift. The general direction over longer time span is up, while shorter time span is more random (like a coin flip).
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.