The following information relates to Happy Company's defined benefit pension plan during the current reporting year:

Plan assets at fair value, January 1	$600,000,000
Expected return on plan assets	50,000,000
Actual return on plan assets	40,000,000
Contributions to the pension fund (end of year)	90,000,000
Amortization of net loss	0
Pension benefits paid (end of year)	32,000,000
Pension expense	60,000,000

Required: Determine the balance of pension plan assets at fair value on December 31.

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