If you see on your dashboard or in the balance by day report a dip like this one please do a recalculation first:
Go to "Enter Coins" page and single click on a coin name in the oldest (first) transaction of your account.
In the open field, delete one letter (e.g. the last letter of BTC to BT) and then add it again (BT back to BTC).
Then go to the dashboard or any other page and the software will ask you to recalculate (bottom right)