SEGMENT INFORMATION

We primarily operate in one reportable business segment, which is NW Natural's local gas distribution business and is referred to as the NGD segment. During the second quarter of 2018, we moved forward with long-term strategic plans, which include a shift away from the California gas storage business, by entering into a Purchase and Sale Agreement that provides for the sale of all of the membership interests in Gill Ranch, subject to various regulatory approvals and closing conditions. As such, we reevaluated reportable segments and concluded that the remaining gas storage activities no longer meet the requirements of a reportable segment. Interstate Storage Services and asset management activities at the Mist gas storage facility, are now reported as other under NW Natural. NW Natural and NW Holdings also have investments and business activities not specifically related to the NGD, which are aggregated and reported as other and described below for each entity.

Natural Gas Distribution

NW Natural's local gas distribution segment is a regulated utility principally engaged in the purchase, sale, and delivery of natural gas and related services to customers in Oregon and southwest Washington. In addition to NW Natural's local gas distribution business, the NGD segment also includes the portion of the Mist underground storage facility used to serve NGD customers, the North Mist gas storage expansion in Oregon, and NWN Gas Reserves, which is a wholly-owned subsidiary of Energy Corp.

NW Natural

NW Natural's activities in Other include Interstate Storage Services and third-party asset management services for the Mist facility in Oregon, appliance retail center operations, and corporate operating and non-operating revenues and expenses that cannot be allocated to NGD operations.

Earnings from Interstate Storage Services assets are primarily related to firm storage capacity revenues. Earnings from the Mist facility also include revenue, net of amounts shared with NGD customers, from management of NGD assets at Mist and upstream pipeline capacity when not needed to serve NGD customers. Under the Oregon sharing mechanism, NW Natural retains 80% of the pre-tax income from these services when the costs of the capacity were not included in NGD rates, or 10% of the pre-tax income when the costs have been included in these rates. The remaining 20% and 90%, respectively, are recorded in a deferred regulatory account for crediting back to NGD customers.

NW Holdings

NW Holdings' activities in Other include all remaining activities not associated with NW Natural, specifically NWN Water, which consolidates the water operations and is pursuing other investments in the water sector itself and through its wholly-owned subsidiaries, NWN Gas Storage, a wholly-owned subsidiary of NWN Energy, NWN Energy's equity investment in TWH, which is pursuing development of a cross-Cascades transmission pipeline project (TWP), and other pipeline assets in NNG Financial. For more information on TWP, see Note 13. Other also includes corporate revenues and expenses that cannot be allocated to other operations.

All prior period amounts have been retrospectively adjusted to reflect the change in reportable segments and the designation of Gill Ranch as a discontinued operation for NW Holdings, and the designation of subsidiaries previously owned by NW Natural that are now owned by NW Holdings as discontinued operations for NW Natural.

Segment Information Summary

Inter-segment transactions were immaterial for the periods presented. The following table presents summary financial information concerning the reportable segments of continuing operations. See Note 17 for information regarding discontinued operations for NW Holdings and NW Natural.



	Three Months Ended March 31,
In thousands	NGD		Other (NW Natural)		NW Natural		Other (NW Holdings)			NW Holdings
2019
Operating revenues	$	279,041	$	5,805	$	284,846	$	502		$	285,348
Depreciation and amortization	21,249		255		21,504		68			21,572
Income (loss) from operations	72,898		3,746		76,644		(599		)	76,045
Net income (loss) from continuing operations	41,206		2,689		43,895		(477		)	43,418
Capital expenditures	48,606		52		48,658		106			48,764
Total assets at March 31, 2019⁽¹⁾	3,091,062		49,566		3,140,628		35,857			3,176,485
2018
Operating revenues	$	257,933	$	5,702	$	263,635	$	—		$	263,635
Depreciation and amortization	20,543		325		20,868		7			20,875
Income from operations	64,756		2,982		67,738		13			67,751
Net income (loss) from continuing operations	39,883		2,131		42,014		(3		)	42,011
Capital expenditures	56,894		435		57,329		—			57,329
Total assets at March 31, 2018⁽¹⁾	2,952,294		50,850		3,003,144		13,824			3,016,968
Total assets at December 31, 2018⁽¹⁾	3,141,969		50,767		3,192,736		36,657			3,229,393


⁽¹⁾	Total assets for NW Holdings exclude assets related to discontinued operations of $14.6 million, $12.4 million, and $13.3 million as of March 31, 2019, March 31, 2018, and December 31, 2018, respectively. Total assets for NW Natural exclude assets related to discontinued operations of $30.5 million as of March 31, 2018.

Natural Gas Distribution Margin

NGD margin is a financial measure used by the Chief Operating Decision Maker (CODM), consisting of NGD operating revenues, reduced by the associated cost of gas, environmental remediation expense, and revenue taxes. The cost of gas purchased for NGD customers is generally a pass-through cost in the amount of revenues billed to regulated NGD customers. Environmental remediation expense represents collections received from customers through the environmental recovery mechanism in Oregon as well as adjustments for the environmental earnings test. This is offset by environmental remediation expense presented in in operating expenses. Revenue taxes are collected from NGD customers and remitted to taxing authorities. The collections from customers are offset by the expense recognition of the obligation to the taxing authority. By subtracting cost of gas, environmental remediation expense, and revenue taxes from NGD operating revenues, NGD margin provides a key metric used by the CODM in assessing the performance of the NGD segment.

The following table presents additional segment information concerning NGD margin:



	Three Months Ended March 31,
In thousands	2019		2018
NGD margin calculation:
NGD operating revenues	$	279,041	$	257,933
Less: NGD cost of gas	105,513		108,164
Environmental remediation expense	8,947		4,624
Revenue taxes	11,926		12,429
NGD margin	$	152,655	$	132,716