At the moment, the bank account graphs on the dashboard are drawn from the balance in each account at the end of the month.
For payment processor accounts such as PayPal and Stripe, the graph is not very informative (for example my Stripe graph shows a straight line of zero, because I do not have any transactions which straddle the month end).
It would make more sense to offer the option to set the graphs to display either the month end balance OR the total amounts received during that month.