11. Segment Information Our reportable segments reflect the significant components of our operations where discrete financial information is evaluated separately by our chief operating decision maker (CODM). We organize our segments based primarily upon the nature of the underlying products and services, as well as the drivers of profitability growth. The net income for each reportable segment included in the table below are in conformity with GAAP and our significant accounting policies as denoted in Note 2. The amounts not attributable to reportable segments are aggregated under other items not allocated to segments. Following is a description of and basis for presentation for each of our reportable segments. Self-Storage Operations The Self-Storage Operations segment reflects the rental operations from all self-storage facilities we own. Our CODM reviews the net operating income (NOI) of this segment, which represents the related revenues less cost of operations (prior to depreciation expense), in assessing performance and making resource allocation decisions. The presentation in the tables below sets forth the NOI of this segment, as well as the depreciation expense for this segment, which while reviewed by our CODM and included in net income, is not considered by the CODM in assessing performance and decision making. For all periods presented, substantially all of our real estate facilities, goodwill and other intangible assets, other assets, and accrued and other liabilities are associated with the Self-Storage Operations segment. Ancillary Operations The Ancillary Operations segment reflects the sale of merchandise and reinsurance of policies against losses to goods stored by our self-storage tenants, activities which are incidental to our primary self-storage rental activities. Our CODM reviews the NOI of these operations in assessing performance and making resource allocation decisions. Investment in PSB This segment represents our 42 % equity interest in PSB, a publicly-traded REIT that owns, operates, acquires and develops commercial properties, primarily multi-tenant flex, office, and industrial space. PSB has a separate management team and board of directors that makes its financing, capital allocation, and other significant decisions. In making resource allocation decisions with respect to our investment in PSB, the CODM reviews PSBs net income, which is detailed in PSBs periodic filings with the SEC. The segment presentation in the tables below includes our equity earnings from PSB. Investment in Shurgard This segment represents our equity interest in Shurgard, a publicly held company which owns and operates self-storage facilities located in seven countries in Western Europe. Shurgard has a separate management team and board of trustees that makes its financing, capital allocation, and other significant decisions. In making resource allocation decisions with respect to our investment in Shurgard, the CODM reviews Shurgards net income. The segment presentation below includes our equity earnings from Shurgard. Presentation of Segment Information The following tables reconcile NOI (as applicable) and net income of each segment to our consolidated net income (amounts in thousands): For the Years Ended December 31, 2019 2018 2017 Self-Storage Segment Revenue $ 2,684,552 $ 2,597,607 $ 2,512,433 Cost of operations ( 752,579 ) ( 695,731 ) ( 657,633 ) Net operating income 1,931,973 1,901,876 1,854,800 Depreciation and amortization ( 512,918 ) ( 483,646 ) ( 454,526 ) Net income 1,419,055 1,418,230 1,400,274 Ancillary Segment Revenue 162,271 156,673 156,095 Cost of operations ( 44,204 ) ( 43,991 ) ( 50,345 ) Net operating income 118,067 112,682 105,750 Investment in PSB Segment Equity in earnings of unconsolidated real estate entities (a) 54,090 89,362 46,544 Investment in Shurgard Segment Equity in earnings of unconsolidated real estate entities (a) 15,457 14,133 25,948 Gain due to Shurgard public offering - 151,616 - Net income from Investment in Shurgard Segment 15,457 165,749 25,948 Total net income allocated to segments 1,606,669 1,786,023 1,578,516 Other items not allocated to segments: General and administrative ( 71,983 ) ( 118,720 ) ( 82,882 ) Interest and other income 28,436 26,442 18,771 Equity in earnings of unconsolidated real estate entities - Other Investments (a) - - 3,163 Interest expense ( 45,641 ) ( 32,542 ) ( 12,690 ) Foreign currency exchange gain (loss) 7,829 18,117 ( 50,045 ) Casualty loss - - ( 7,789 ) Gain on sale of real estate 341 37,903 1,421 Net income $ 1,525,651 $ 1,717,223 $ 1,448,465 (a) See Note 4 for a reconciliation of these amounts to our total Equity in Earnings of Unconsolidated Real Estate Entities on our income statements.