Hello world! Long-time lurker here in need of some help. Is it possible to adjust the options pricing model on TWS to only count trading days (252 day-count)? The risk-navigator and the strategy performance profile count weekends as well which will result in calendarized structures giving wrong 1st expiry PnL curve. If it is not possible to change the trading day count can I just adjust the vol accordingly using the variance-time formula? Or am I doomed to come up with a spreadsheet to do the options PnL simulator myself?
That's disappointing that IB doesn't use trading day convention for equities. For FX and interest rates, i think calendar days is the standard convention. I wouldn't tweak the vol. It will give weird results. Building a simulator in Excel is pretty easy and in my opinion worthwhile if you are going to trade volatility as a sophisticated retail trader.
Is a simpler solution to open a brokerage account with another broker that does it right? Any recommendations?