Other Investments

Nuclear Decommissioning Trusts

Future decommissioning costs of removal of SCE's nuclear assets are expected to be funded from independent decommissioning trusts, which currently receive contributions of approximately $23 million per year through SCE customer rates. Contributions to the decommissioning trusts are reviewed every three years by the CPUC. During 2012, SCE filed with the CPUC a nuclear decommissioning cost application which includes the 2011 San Onofre and 2010 Palo Verde site-specific decommissioning studies. If the CPUC approves the studies, the annual trust contributions are expected to increase to $41 million in 2014. If additional funds are needed for decommissioning, it is probable that the additional funds will be recoverable through customer rates. Funds collected, together with accumulated earnings, will be utilized solely for decommissioning. The CPUC has set certain restrictions related to the investments of these trusts.

The following table sets forth amortized cost and fair value of the trust investments:



	Longest Maturity Dates	Amortized Cost				Fair Value
(in millions)	Longest Maturity Dates	March 31, 2013		December 31, 2012		March 31, 2013		December 31, 2012
Stocks	—	$	990	$	978	$	2,468	$	2,271
Municipal bonds	2051	509		518		631		644
U.S. government and agency securities	2043	590		547		646		603
Corporate bonds	2054	327		324		408		410
Short-term investments and receivables/payables	One-year	89		116		93		120
Total		$	2,505	$	2,483	$	4,246	$	4,048

Trust fund earnings (based on specific identification) increase the trust fund balance and the ARO regulatory liability. Proceeds from sales of securities (which are reinvested) were $435 million and $602 million for the three months ended March 31, 2013 and 2012, respectively. Unrealized holding gains, net of losses, were $1.7 billion and $1.6 billion at March 31, 2013 and December 31, 2012, respectively.

The following table sets forth a summary of changes in the fair value of the trust:



	Three months ended March 31,
(in millions)	2013			2012
Balance at beginning of period	$	4,048		$	3,592
Gross realized gains	5			25
Gross realized losses	(1		)	(4		)
Unrealized gains, net	176			184
Other-than-temporary impairments	(8		)	(5		)
Interest, dividends, contributions and other	26			61
Balance at end of period	$	4,246		$	3,853

Due to regulatory mechanisms, earnings and realized gains and losses (including other-than-temporary impairments) have no impact on operating revenue or earnings.