Please make sure you are plotting this indicator on DAILY bars, not doing so will lead to unintended results. Also, make sure that you keep up to date the Risk-free interest rate, which you can consult (for U.S.) on ycharts.com.
This is an indicator that is meant to be used for Options Day Trading, but it can be useful for mid-term or leaps for I also enabled...
Monthly options expiration for the year 2020.
Also you can set a flag X no. of days before the expiration date. I use it at as marker to take off existing positions in expiration week or roll to next expiration date or to place new trades.
Happy new year 2020 and all the best traders.