A company takes out a four-year, $800,000 mortgage on May 1, The interest rate on the loan is 5% per year, and blended payments of $18,423 (including both interest and principal) are to be made at the end of each month. The following is an extract from the loan amortization table the bank provided the company: Beginning Ending Loan Loan Balance Payment Interest Principal $800,000 $18,423 $3,333 $15,090 15,153 15,216 15,280 Balance Payment 1 Payment 2 Payment 3 Payment 4 784,910 769,757 754,541 18,423 18,423 18,423 3,270 3,207 3,143 784,910 769,757 754,541 739,261 (a) The monthly payments will be the same amount each month, throughout the entire term of the loan. From the loan amortization table, we can see that the portion of the payment related to interest is decreasing each payment. Prepare a brief explanation for why this is happening