Offer your thoughts or opinion on the input financial query or topic using your financial background.

How to split stock earnings?
If you have been a good steward of your friend's money this suggestion will not be too difficult. Pay your friend what his money would have earned in the S&P 500 if you had just invested it in an index fund. Subtract 15% for long-term capital gains. You can use the ticker SPY to see what the price was on the day he gave you the money, versus the price today. If you had helped your friend open an account for himself, you would have given him more than the returns on his money, you would have helped educate him on how to invest for himself.