Defined benefit liability is the net total of the following amounts:
(a) the present value of the defined benefit obligation at the end of the reporting period;
(b) plus any actuarial gains (less any actuarial losses) not recognised;
(c) minus any past service cost not yet recognised;
(d) minus the fair value at the end of the reporting period of plan assets (if any) out of which the obligations are to be settled directly.
Source: IAS 19 Employee Benefits.