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"A 3/27 Adjustable-Rate Mortgage (ARM), also known as a 3/27 ARM, is a type of mortgage loan with an initial fixed interest rate for the first three years, followed by an adjustable interest rate for the remaining 27 years of the loan term. It is a specific variation of an adjustable-rate mortgage."
Here's how a 3/27 ARM works:
It's important to note that 3/27 ARMs can be riskier than traditional fixed-rate mortgages, especially if interest rates rise significantly after the initial fixed-rate period. Borrowers who opt for this type of mortgage should carefully consider their ability to manage potential payment increases in the future. Some 3/27 ARMs may also have a prepayment penalty, which could apply if the borrower decides to refinance or pay off the mortgage early.
As with any mortgage, borrowers should fully understand the terms and risks associated with the 3/27 ARM before entering into such a loan agreement. It is essential to read and comprehend the loan documents, including the Truth in Lending disclosure, to know how the interest rate will adjust and what the potential future payments might be.
Let's go through a numerical example of a 3/27 Adjustable-Rate Mortgage (ARM) to illustrate how it works. For this example, we'll consider a hypothetical mortgage with the following terms:
Loan Amount: $200,000
Initial Fixed Rate Period: 3 years
Adjustable Rate Period: 27 years
Initial Fixed Interest Rate: 4% per annum
Margin: 2%
Index: 1-Year U.S. Treasury Bill rate
Frequency of Adjustment: Annually
Step 1: Initial Fixed Rate Period (3 years):
During the first three years of the mortgage, the interest rate is fixed at 4% per annum.
Monthly Payment during the initial fixed-rate period:
To calculate the monthly payment, we'll use the formula for a fixed-rate mortgage:
Monthly Interest Rate = Annual Interest Rate / 12
Monthly Interest Rate = 4% / 12 ≈ 0.3333% (rounded to 4 decimal places)
Number of Monthly Payments during the initial fixed-rate period = 3 years * 12 months/year = 36 months
Monthly Payment = (Loan Amount * Monthly Interest Rate) / (1 - (1 + Monthly Interest Rate)^(-Number of Monthly Payments))
Monthly Payment = ($200,000 * 0.003333) / (1 - (1 + 0.003333)^(-36)) Monthly Payment = $946.67
Step 2: Adjustable-Rate Period (27 years):
After the initial 3-year fixed-rate period, the mortgage enters the adjustable rate period. The interest rate will now adjust annually based on the 1-Year U.S. Treasury Bill rate plus the margin of 2%.
Let's assume that at the end of the 3-year fixed-rate period, the 1-Year U.S. Treasury Bill rate is 3%.
Annual Interest Rate for Year 4 = 1-Year U.S. Treasury Bill Rate + Margin
Annual Interest Rate for Year 4 = 3% + 2% = 5%
Monthly Interest Rate for Year 4 = 5% / 12 = 0.4167% (rounded to 4 decimal places)
Number of Monthly Payments during the adjustable rate period = 27 years * 12 months/year = 324 months
Monthly Payment for Year 4 and beyond:
Monthly Payment = (Loan Amount * Monthly Interest Rate) / (1 - (1 + Monthly Interest Rate)^(-Number of Monthly Payments))
Monthly Payment = ($200,000 * 0.004167) / (1 - (1 + 0.004167)^(-324)) Monthly Payment = $1,087.12
As the 3/27 ARM enters the adjustable rate period, the monthly payment increases from approximately $946.67 to approximately $1,087.12. This increase is due to the adjustment in the interest rate based on the 1-Year U.S. Treasury Bill rate plus the margin of 2%.
It's important to note that the 1-Year U.S. Treasury Bill rate can fluctuate from year to year, which means that the interest rate and the monthly payment in subsequent years can vary depending on changes in the index. Borrowers should be prepared for potential payment fluctuations in the adjustable-rate period.