The tutorial shows how to build an amortization schedule in Excel to detail periodic payments on an amortizing loan or mortgage. Fill in the "Period" column.Fill in the column titled "Period" with your payment dates. Loan amortization schedule. 3. 4, Enter values, Loan summary. This Excel spreadsheet makes it easy to view the amortization of a home loan with optional extra monthly payments. Does anyone know how to calculate the principal and interest payments after a one time extra principal payment on a mortgage in excel? Payments based on CalPERS amortization tables. The Guidelines do not include any additional provisions related to implementation of linkage fees beyond those specified in the. Ordinance and Resolution.