Set up three "other income accounts"
1) Taxable dividends/interest
2) Unrealized gains/losses
3) Realized gains/losses
You only record realized gains/losses when you sell investments. Your statement should show taxable dividends and interest which is usually reinvested. Unrealized gains/losses is the change in market value. Make a journal entry to record the change in value from the previous for the total in the investment account. Credit any taxable dividends/interest. If no sales have been made the difference is unrealized gains/losses. Sales only occur when money is withdrawn from the account. Sales between funds within the investment accounts are just transfers within the account and are not recorded on the books.
