A shortage is not the same thing as a deficiency
A shortage generally means the escrow balance is below the target amount at the time of analysis, while a deficiency involves a negative balance. The exact treatment depends on current servicing rules and the loan circumstances, so the calculation should be paired with the applicable requirements.
A surplus means projected or actual funds exceed the required amount
A surplus occurs when the account contains more than the amount required under the analysis. Whether and how that amount must be refunded depends on the governing rules and account status.
The month of the low point matters
Two accounts with the same annual taxes and insurance can require different starting balances if the bills are due in different months. That is why simply adding the annual expenses and dividing by twelve does not fully reproduce an aggregate escrow analysis.
Recalculate when taxes or insurance change
Escrow projections depend on expected disbursements. A new tax bill, insurance renewal, or other material change can alter the monthly deposit and the projected low point. Save the underlying assumptions so the calculation can be reviewed later.
Use software when the calculation becomes repetitive
Prepare initial and annual escrow disclosures and perform a 12-month aggregate escrow analysis on your Windows computer.