MCKESSON CORP
| 2013 | FY |
Years Ended March 31,
(In millions)
2013
2012
Benefit obligation at beginning of period
$
144
$
152
Service cost
2
2
Interest cost
6
7
Actuarial gain
(9
)
(4
)
Benefit payments
(12
)
(13
)
Benefit obligation at end of period
$
131
$
144
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