The trial balance of Pacilio Security Services, Inc. as of January 1, Year 10, had the following normal balances:

Cash	$122,475
Petty cash	100
Accounts receivable	27,400
Allowance for doubtful accounts	4,390
Supplies	165
Prepaid rent	3,000
Merchandise inventory (38 @ $290)	11,020
Equipment	9,000
Van	27,000
Accumulated depreciation	23,050
Sales tax payable	290
Employee income tax payable	500
FICA Social Security tax payable	600
FICA Medicare tax payable	150
Warranty payable	312
Unemployment tax payable	630
Interest payable	320
Notes payable	12,000
Common stock	50,000
Retained earnings	107,918

During Year 10, Pacilio Security Services experienced the following transactions:

1

1. On September 1, paid the note and interest owed to State Bank.

Notes Payable (L-)	12,000
Interest Payable (L-)	320
Interest Expense ($12,000 x 8% x 8/12) (E+ or SE-)	640
Cash		12,960

can someone explain where did the 8% came from ?