A couple of Greeks questions here. I'm using IB, and I have theta columns in TWS as theta and position theta. What is the difference between the numbers in these two columns in IB and what do they represent? Dollars? Next: Is there any way of going back to the trade opening, earlier in the day, and seeing what my theta and theta position was? Lastly, been reading about the theta ratio (theta/net portfolio liquidity) and was wondering if I just total my thetas? Use the portfolio thetas? And what is meant by net portfolio liquidity? Cash only? Account balance? Thanks in advance for any help you can provide on this.