Pensions and Post Retirement Benefits

The funded status of the company's defined benefit pension and post retirement plans at December 31 were as follows:



	Defined benefit pension plans				Defined benefit post retirement plans
	2019		2018		2019		2018
Benefit obligation	(789.4	)	(803.7	)	(125.4	)	(112.3	)
Fair value of plan assets	605.8		726.9		—		—
Funded status of plans - deficit	(183.6	)	(76.8	)	(125.4	)	(112.3	)
Impact of asset ceiling	0.3		—		—		—
Net accrued liability⁽¹⁾	(183.3	)	(76.8	)	(125.4	)	(112.3	)



Weighted average assumptions used to determine benefit obligations:
Discount rate	3.0	%	3.6	%	3.3	%	4.2	%
Rate of compensation increase	2.6	%	2.7	%	3.6	%	3.6	%
Health care cost trend	—		—		4.5	%	4.6	%


(1)	The defined benefit pension plan net accrued liability at December 31, 2019 of $183.3 (December 31, 2018 - $76.8) was comprised of pension surpluses of $51.9 and pension deficits of $235.2 (December 31, 2018 - $64.0 and $140.8). See notes 13 and 14.

Pension and post retirement benefit expenses recognized in the consolidated statement of earnings for the years ended December 31 were as follows:



	2019	2018
Defined benefit pension plan expense	18.8	26.8
Defined contribution pension plan expense	53.1	50.3
Defined benefit post retirement plan expense	8.4	9.7
	80.3	86.8

Pre-tax actuarial net gains (losses) recognized in the consolidated statement of comprehensive income for the years ended December 31 were comprised as follows:



	2019		2018
Defined benefit pension plans
Actuarial net gains (losses) on plan assets and change in asset ceiling	18.8		(69.2	)
Actuarial net gains (losses) on benefit obligations	(109.9	)	74.1
	(91.1	)	4.9
Defined benefit post retirement plans - actuarial net gains (losses) on benefit obligations	(8.0	)	7.3
	(99.1	)	12.2

During 2019 the company contributed $36.8 (2018 - $28.8) to its defined benefit pension and post retirement plans, and expects to contribute $19.3 in 2020.