Defined benefit obligation, 31 December 20X1	$	166,000
Benefits paid to retirees in 20X2 during the year		34,000
Current service cost for 20X2		8,700
Actual return on plan assets for 20X2		4,000
Fair value of plan assets, 31 December 20X1		98,000
Funding payment 1, December 20X2		9,000
Past service cost from amendment dated 31 December 20X2; liability is increased because benefits were increased on a retrospective basis		5,700
Actuarial revaluation dated 31 December 20X2; decrease to liability because of changed mortality assumptions		(4,500	)
Long-term interest rate on corporate bonds		7	%

How do I calculate defined benefit obligation for December 31, 20x2 with this information? I am having trouble