As of December 31, 2019, the pension plan assets measured at fair value on a recurring basis were as follows:



	Quoted Prices		Significant
	in Active		Other		Significant
	Markets for		Observable		Unobservable
	Identical Inputs		Inputs		Inputs
Millions	(Level 1)		(Level 2)		(Level 3)		Total
Plan assets at fair value:
Temporary cash investments	$	6	$	1	$	-	$	7
Registered investment companies [a]		9		-		-		9
Federal government securities		-		202		-		202
Bonds and debentures		-		575		-		575
Corporate stock		1,932		7		-		1,939
Total plan assets at fair value	$	1,947	$	785	$	-	$	2,732
Plan assets at NAV:
Registered investment companies [b]								285
Venture capital and buyout partnerships								531
Real estate funds								261
Collective trust and other funds								707
Total plan assets at NAV							$	1,784
Other assets/(liabilities) [c]								12
Total plan assets							$	4,528

As of December 31, 2018, the pension plan assets measured at fair value on a recurring basis were as follows:



	Quoted Prices		Significant
	in Active		Other		Significant
	Markets for		Observable		Unobservable
	Identical Inputs		Inputs		Inputs
Millions	(Level 1)		(Level 2)		(Level 3)		Total
Plan assets at fair value:
Temporary cash investments	$	21	$	-	$	-	$	21
Registered investment companies [a]		1		-		-		1
Federal government securities		-		191		-		191
Bonds and debentures		-		538		-		538
Corporate stock		1,355		12		-		1,367
Total plan assets at fair value	$	1,377	$	741	$	-	$	2,118
Plan assets at NAV:
Registered investment companies [b]								378
Venture capital and buyout partnerships								443
Real estate funds								222
Collective trust and other funds								745
Total plan assets at NAV							$	1,788
Other assets/(liabilities) [c]								(19)
Total plan assets							$	3,887

[a]Registered investment companies measured at fair value are stock investments.

[c]Other assets include accrued receivables, net payables, and pending broker settlements.

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Tabular disclosure of cash contributions for qualified pension plan benefit plans and non-qualified pension and OPEB plans.

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Tabular disclosure of benefit obligation and plan assets of defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall.

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