I had to relook at this because I did the code a long time ago. The metric I rely on most is basically your second calculation (so thank you for the post) but I add each parcel up individually and for capital additions I use the exact fraction of the period that they apply within the period being reported. I use constant dollars which makes returns look better over long periods than they are. I include all brokerage and associated fees and taxes on these, but only consider shares and options and ignore returns on cash and/or interest on borrowings (which would also reduce my overall return if I included it). Correction also is that my figure above is a simple return (i.e. 67%/10) not a compound return so no gold star for me over the 10 years - I am more like 5.3% compound. I read a lot about the impending GFC and made the wrong judgement that it wasn't going to be that big a deal - I lost a massive amount and didn't recover the capital I lost until 17Jan13.
