It would be cool to add detrended Buffet Indicator adujstment for back testing in the advanced settings of backtest set-up page. Detrended Buffet Indicator can be looked at as the oscillator which shows whether is stock market overvalued compared to the GDP. And it could be used for the cash allocation if the portfolio is adjusted on yearly or quaterly basis.
You can find more about indicator here:
https://www.currentmarketvaluation.com/models/buffett-indicator.php
What do you think about that adjustment?