AES CORP | 2013 | FY | 3

The table below summarizes the significant weighted average assumptions used in the calculation of benefit obligation and net periodic benefit cost, both domestic and foreign, as of December 31, 2013 and 2012:
 
 
2013
 
2012
 
 
 
U.S.
 
Foreign
 
U.S.
 
Foreign
 
Benefit Obligation:
 
 
 
 
 
 
 
 
 
Discount rates
 
4.89
%
 
10.80
%
(2) 
3.86
%
 
8.28
%
(2) 
Rates of compensation increase
 
3.94
%
(1) 
6.44
%
 
3.94
%
(1) 
6.47
%
 
Periodic Benefit Cost:
 
 
 
 
 
 
 
 
 
Discount rate
 
3.86
%
 
8.28
%
 
4.67
%
 
9.54
%
 
Expected long-term rate of return on plan assets
 
7.15
%
 
11.16
%
 
7.28
%
 
10.81
%
 
Rate of compensation increase
 
3.94
%
(1) 
6.47
%
 
3.94
%
(1) 
5.99
%
 

(1)
A U.S. subsidiary of the Company has a defined benefit obligation of $651 million and $764 million as of December 31, 2013 and 2012, respectively, and uses salary bands to determine future benefit costs rather than rates of compensation increases. Rates of compensation increases in the table above do not include amounts related to this specific defined benefit plan.
(2) 
Includes an inflation factor that is used to calculate future periodic benefit cost, but is not used to calculate the benefit obligation.

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