/* rexx */
principal = -1
do UNTIL principal >= 0
say "Input Loan Amount: "
parse pull principal
end
if principal = 0 then do
say "Principal is zero, exiting"
exit
end
principalNoExtra = principal
periodicRate = -1
Do UNTIL periodicRate > 0
Say "Enter Yearly Interest Rate:"
parse pull periodicRate
End
periodicRate = (periodicRate / 100) / 12
numPayments = -1
Do UNTIL numPayments > 0
Say "Enter the Number of years:"
parse pull numPayments
End
numPayments = numPayments * 12
extraPmt = -1
Do UNTIL extraPmt >= 0
Say "Enter the extra payment amount per term (0 if none):"
parse pull extraPmt
End
outputType = 0
Do until outputType = 1 | outputType = 2
Say "Enter 1 for text or 2 for html"
parse pull outputType
End
Say "Enter output filename (without extension):"
parse pull filename
if outputType = 1 then
filename = filename || ".txt"
else
filename = filename || ".html"
call LINEOUT filename, "" /* Open file for writing */
numerator = principal * periodicRate * ((1 + periodicRate) ** numPayments)
denominator = ((1 + periodicRate) ** numPayments) - 1
paymentAmt = numerator / denominator
if outputType = 2 then do
call LINEOUT filename, ""
call LINEOUT filename, ""
call LINEOUT filename, ""
call LINEOUT filename, ""
call LINEOUT filename, ""
call LINEOUT filename, "| Period | Beginning Principal | Payment Amount | Extra Payment | Total Interest | New Principal |
|---|
"
end
else do
call LINEOUT filename, "--------- AMORTIZATION SCHEDULE ---------"
call LINEOUT filename, "Initial Principal: $" principal
call LINEOUT filename, "Payment Amount: $" paymentAmt
call LINEOUT filename, ""
call LINEOUT filename, "Period | Beginning Principal | Payment Amount | Extra Payment | Total Interest | New Principal"
end
principal2 = principal
totalPaid2 = 0
j = 0
numpay = 1
interestPaid2 = 0
do while principal2 > 0
j = j + 1
beginningPrincipal = principal2
IntPmt2 = principal2 * periodicRate
principalPmt2 = (paymentAmt - IntPmt2) + extraPmt
if principal2 < principalPmt2 then do
principalPmt2 = principal2
numpay = j
IntPmt2 = principal2 * periodicRate
end
principal2 = principal2 - principalPmt2
totalPaid2 = totalPaid2 + principalPmt2 + IntPmt2
interestPaid2 = interestPaid2 + IntPmt2
if outputType = 2 then do
call LINEOUT filename, "| "j" | $"beginningPrincipal" | $"paymentAmt" | $"extraPmt" | $"interestPaid2" | $"principal2" |
"
end
else do
call LINEOUT filename, j " | $" beginningPrincipal " | $" paymentAmt " | $" extraPmt " | $" interestPaid2 " | $" principal2
end
end
interestNoExtra = 0
principalTerm = 0
g = 0
do while principalNoExtra > 0
g = g + 1
interest_term = principalNoExtra * periodicRate
principalTerm = paymentAmt - interest_term
if principalNoExtra < principalTerm then
principalTerm = principalNoExtra
principalNoExtra = principalNoExtra - principalTerm
interestNoExtra = interestNoExtra + interest_term
end
totalExtraPaid = extraPmt * numpay
ROI = 0
if totalExtraPaid > 0 then do
ROI = (interestNoExtra - interestPaid2) / totalExtraPaid
end
if extraPmt = 0 then do
ROI = 0
end
if outputType = 2 then do
call LINEOUT filename, "
"
call LINEOUT filename, "Total Paid Accelerated ($" extraPmt " per payment): $" totalPaid2 "
"
call LINEOUT filename, "Average ROI:" ROI * 100 "%
"
end
else do
call LINEOUT filename, ""
call LINEOUT filename, "Total Paid Accelerated ($" extraPmt " per payment): $" totalPaid2
call LINEOUT filename, "Average ROI per payment (interest avoided): " ROI * 100 "%"
end
call LINEOUT filename /* Close file */
say "Output written to:" filename