This is a methodology that Buffett uses to measure value.
Recommend turning off most plots and just plotting PE and/or PE10 percent difference only.
The "slope and intercept" inputs should be left alone unless you recalculate them with updated data.
The "current PE and PE10" inputs can be found here: https://www.multpl.com/s-p-500-pe-ratio This is a daily estimated value.
The full calculated value is released once per month, and is what Quandl has. Change these numbers if you want today's updated values.
Once you have the study set up the way you want, I recommend saving the defaults (bottom left corner in the settings screen).
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.