Why is my amortization schedule "unbalanced"?

When measuring a lease, you might notice that your amortization schedule says that it is "unbalanced" (see below).

Any lease that commences or ends on a day other than the 1st of a given month will be "unbalanced." What this means is that there is an extremely small residual balance  that is derived from pro-rata rounding.

The residual balance is normally written off to the Income Statement at the end of the lease term.