Joe has took an amortised loan for 5 years at 4% per annum compounding quarterly.Each quarterly payment is for $12,000.Joe has just paid the 14^th payment and has renegotiated its loan with the bank. The interest rate and compounding period remain the same, but the loan time frame is extended so that, instead of there being 6 further payments, there will be 20 more payments to be made. By how much does the quarterly payment Joe will now make decrease from the original quarterly payment?