NOTE 9 - SUPPLEMENTAL FINANCIAL STATEMENT INFORMATION

Temporary Investments

Temporary investments with an original maturity of three months or less are treated as cash equivalents and are stated at cost. Temporary investments totaled $449 million and $402 million at March 31, 2019 and December 31, 2018, respectively.

Accounts and Notes Receivable



In millions	March 31, 2019		December 31, 2018
Accounts and notes receivable, net:
Trade	$	3,186	$	3,249
Other	307		272
Total	$	3,493	$	3,521

The allowance for doubtful accounts was $82 million and $81 million at March 31, 2019 and December 31, 2018, respectively.

Inventories



In millions	March 31, 2019		December 31, 2018
Raw materials	$	266	$	260
Finished pulp, paper and packaging	1,282		1,241
Operating supplies	637		641
Other	116		99
Total	$	2,301	$	2,241

Plants, Properties and Equipment

Accumulated depreciation was $20.5 billion at March 31, 2019 and December 31, 2018. Depreciation expense was $297 million and $306 million for the three months ended March 31, 2019 and 2018, respectively.

Non-cash additions to plants, property and equipment included within accounts payable were $114 million and $135 million at March 31, 2019 and December 31, 2018, respectively.

Interest

Interest payments made during the three months ended March 31, 2019 and 2018 were $214 million and $223 million, respectively.

Amounts related to interest were as follows:



	Three Months Ended March 31,
In millions	2019		2018
Interest expense	$	184	$	180
Interest income	51		45
Capitalized interest costs	5		8

Asset Retirement Obligations

The Company had recorded liabilities of $90 million and $86 million related to asset retirement obligations at March 31, 2019 and December 31, 2018, respectively.