A partial adjusted trial balance of Crane Company at January 31, 2021, shows the following.

CRANE COMPANY Adjusted Trial Balance January 31, 2021
		Debit		Credit
Supplies		$2,900
Prepaid Insurance		10,500
Salaries and Wages Payable				$3,400
Unearned Revenue				4,200
Supplies Expense		4,300
Insurance Expense		1,750
Salaries and Wages Expense		7,800
Service Revenue				8,600

Answer the following questions, assuming the year begins January 1.

if $6,500 was received in January for services performed in January, what was the balance in Unearned Revenue at December 31, 2020?