UNITEDHEALTH GROUP INC | 2013 | FY | 3

A summary of short-term and long-term investments by major security type is as follows:
(in millions)
 
Amortized
Cost
 
Gross
Unrealized
Gains
 
Gross
Unrealized
Losses
 
Fair
Value
December 31, 2013
 
 
 
 
 
 
 
 
Debt securities - available-for-sale:
 
 
 
 
 
 
 
 
U.S. government and agency obligations
 
$
2,211

 
$
5

 
$
(21
)
 
$
2,195

State and municipal obligations
 
6,902

 
147

 
(72
)
 
6,977

Corporate obligations
 
7,265

 
130

 
(60
)
 
7,335

U.S. agency mortgage-backed securities
 
2,256

 
23

 
(61
)
 
2,218

Non-U.S. agency mortgage-backed securities
 
697

 
12

 
(7
)
 
702

Total debt securities - available-for-sale
 
19,331

 
317

 
(221
)
 
19,427

Equity securities - available-for-sale
 
1,576

 
9

 
(13
)
 
1,572

Debt securities - held-to-maturity:
 
 
 
 
 
 
 
 
U.S. government and agency obligations
 
181

 
1

 
—

 
182

State and municipal obligations
 
28

 
—

 
—

 
28

Corporate obligations
 
334

 
—

 
—

 
334

Total debt securities - held-to-maturity
 
543

 
1

 
—

 
544

Total investments
 
$
21,450

 
$
327

 
$
(234
)
 
$
21,543

December 31, 2012
 
 
 
 
 
 
 
 
Debt securities - available-for-sale:
 
 
 
 
 
 
 
 
U.S. government and agency obligations
 
$
2,501

 
$
38

 
$
(1
)
 
$
2,538

State and municipal obligations
 
6,282

 
388

 
(3
)
 
6,667

Corporate obligations
 
6,930

 
283

 
(4
)
 
7,209

U.S. agency mortgage-backed securities
 
2,168

 
70

 
—

 
2,238

Non-U.S. agency mortgage-backed securities
 
538

 
36

 
—

 
574

Total debt securities - available-for-sale
 
18,419

 
815

 
(8
)
 
19,226

Equity securities - available-for-sale
 
668

 
10

 
(1
)
 
677

Debt securities - held-to-maturity:
 
 
 
 
 
 
 
 
U.S. government and agency obligations
 
168

 
6

 
—

 
174

State and municipal obligations
 
30

 
—

 
—

 
30

Corporate obligations
 
641

 
2

 
—

 
643

Total debt securities - held-to-maturity
 
839

 
8

 
—

 
847

Total investments
 
$
19,926

 
$
833

 
$
(9
)
 
$
20,750

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