AETNA INC /PA/ | 2013 | FY | 3


The following table shows the changes in the benefit obligations during 2013 and 2012 for our pension and OPEB plans.
 
Pension Plans
 
OPEB Plans
(Millions)
2013

2012

 
2013

2012

Benefit obligation, beginning of year
$
6,665.8

$
6,130.3

 
$
292.4

$
312.7

Service cost


 
.1

.1

Interest cost
271.5

298.4

 
11.1

14.4

Actuarial (gain) loss
(653.7
)
550.2

 
(22.5
)
(11.4
)
Benefits paid
(318.3
)
(313.1
)
 
(20.2
)
(23.4
)
Benefit obligation, end of year
$
5,965.3

$
6,665.8

 
$
260.9

$
292.4

 
 
 
 
 
 

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