2013 | 2012 | 2011 | |||||||||
Service cost | $ | (3.2 | ) | $ | (3.0 | ) | $ | (2.4 | ) | ||
Interest cost | (11.9 | ) | (12.6 | ) | (13.4 | ) | |||||
Expected return on plan assets | 15.2 | 14.5 | 13.8 | ||||||||
Amortization of prior service cost | (.2 | ) | (.3 | ) | (.3 | ) | |||||
Recognized net actuarial loss | (6.4 | ) | (6.0 | ) | (4.0 | ) | |||||
Net pension (expense) income | $ | (6.5 | ) | $ | (7.4 | ) | $ | (6.3 | ) | ||
Weighted average assumptions for pension costs: | |||||||||||
Discount rate used in net pension costs | 3.8 | % | 4.4 | % | 5.2 | % | |||||
Rate of compensation increase used in pension costs | 3.8 | % | 3.8 | % | 4.0 | % | |||||
Expected return on plan assets | 6.6 | % | 6.6 | % | 6.7 | % | |||||
Weighted average assumptions for benefit obligation: | |||||||||||
Discount rate used in benefit obligation | 4.6 | % | 3.8 | % | 4.4 | % | |||||
Rate of compensation increase used in benefit obligation | 3.8 | % | 3.8 | % | 3.8 | % | |||||