UNITEDHEALTH GROUP INC | 2013 | FY | 3

A reconciliation of the beginning and ending balances of assets measured at fair value on a recurring basis using Level 3 inputs is as follows:
 
 
December 31, 2013
 
December 31, 2012
 
December 31, 2011
(in millions)
 
Debt
Securities
 
Equity
Securities
 
Total
 
Debt
Securities
 
Equity
Securities
 
Total
 
Debt
Securities
 
Equity
Securities
 
Total
Balance at beginning of period
 
$
17

 
$
224

 
$
241

 
$
208

 
$
209

 
$
417

 
$
141

 
$
208

 
$
349

Purchases
 
38

 
71

 
109

 
11

 
71

 
82

 
92

 
35

 
127

Sales
 
(10
)
 
(25
)
 
(35
)
 
—

 
(34
)
 
(34
)
 
—

 
(17
)
 
(17
)
Settlements
 
—

 
—

 
—

 
(1
)
 
—

 
(1
)
 
(25
)
 
(7
)
 
(32
)
Net unrealized losses in accumulated other comprehensive income
 
(2
)
 
(7
)
 
(9
)
 
—

 
(14
)
 
(14
)
 
—

 
(4
)
 
(4
)
Net realized (losses) gains in investment and other income
 
(1
)
 
6

 
5

 
—

 
13

 
13

 
—

 
(6
)
 
(6
)
Transfers to held-to-maturity
 
—

 
—

 
—

 
(201
)
 
(21
)
 
(222
)
 
—

 
—

 
—

Balance at end of period
 
$
42

 
$
269

 
$
311

 
$
17

 
$
224

 
$
241

 
$
208

 
$
209

 
$
417

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