21. Segment and Geographical Data The Company operates in two reportable segments, which are further described below:  Specialty Brands includes innovative specialty pharmaceutical brands; and  Specialty Generics includes niche specialty generic drugs and API(s). All prior period segment information has been recast to reflect the realignment of the Company's reportable segments on a comparable bases, as previously discussed in Note 1. Management measures and evaluates the Company's operating segments based on segment net sales and operating income. Management excludes corporate expenses from segment operating income. In addition, certain amounts that management considers to be non-recurring or non-operational are excluded from segment operating income because management evaluates the operating results of the segments excluding such items. These items include, but are not limited to, intangible asset amortization, net restructuring and related charges, non-restructuring impairments and separation costs. Although these amounts are excluded from segment operating income, as applicable, they are included in reported consolidated operating (loss) income and in the following reconciliations presented below. Management manages assets on a total company basis, not by operating segment. The Company's chief operating decision maker does not regularly review any asset information by operating segment and, accordingly, the Company does not report asset information by operating segment. Total assets were approximately $10,338.9 million and $10,877.3 million at December 27, 2019 and December 28, 2018 , respectively. Selected information by business segment was as follows: Fiscal Year 2019 2018 2017 Net sales: Specialty Brands $ 2,423.8 $ 2,496.7 $ 2,352.0 Specialty Generics 738.7 718.9 869.6 Net sales 3,162.5 3,215.6 3,221.6 Operating (loss) income: Specialty Brands $ 1,174.5 $ 1,093.1 $ 1,146.3 Specialty Generics 108.1 89.3 266.4 Segment operating income 1,282.6 1,182.4 1,412.7 Unallocated amounts: Corporate and unallocated expenses (1) (137.8 ) (155.8 ) (125.2 ) Intangible asset amortization (853.4 ) (740.2 ) (694.5 ) Restructuring and related charges, net (2) 1.7 (108.2 ) (36.4 ) Non-restructuring impairment charges (388.0 ) (3,893.1 ) (63.7 ) Separation costs (3) (63.9 ) (6.0 )  R&amp;D upfront payment (4) (20.0 )   Opioid-related litigation settlement charge (5) (1,643.4 )   Operating (loss) income $ (1,822.2 ) $ (3,720.9 ) $ 492.9 Depreciation and amortization: Specialty Brands $ 862.4 $ 762.5 $ 712.0 Specialty Generics 88.7 89.6 96.3 $ 951.1 $ 852.1 $ 808.3 (1) Includes administration expenses and certain compensation, legal, environmental and other costs not charged to the Company's reportable segments. (2) Includes restructuring-related accelerated depreciation. (3) Represents costs incurred related to the separation of the Company's Specialty Generics segment, inclusive of costs related to the suspended spin-off of that business and rebranding costs associated with the Specialty Brands ongoing transformation, all of which are included in SG&amp;A. (4) Represents R&amp;D expense incurred related to an upfront payment made to Silence in connection with the license and collaboration agreement entered into in July 2019. See Note 6 for further information. (5) Subsequent to December 27, 2019, the Company announced an agreement in principle on the terms of a global settlement of all opioid-related claims against the Company and its subsidiaries. See Note 24 for further information. Net sales by product family within the Company's reportable segments were as follows: Fiscal Year 2019 2018 2017 Acthar Gel $ 952.7 $ 1,110.1 $ 1,195.1 INOmax 571.4 542.7 505.2 Ofirmev 384.0 341.9 302.5 Therakos 246.9 231.2 214.9 Amitiza (1) 208.5 183.8  BioVectra (2) 40.1 53.1 54.7 Other 20.2 33.9 79.6 Specialty Brands 2,423.8 2,496.7 2,352.0 Hydrocodone (API) ad hydrocodone-containing tablets 76.3 65.9 85.3 Oxycodone (API) and oxycodone-containing tablets 74.9 66.1 88.0 Acetaminophen (API) 189.9 192.7 185.5 Other controlled substances 352.5 343.8 412.0 Other 45.1 50.4 98.8 Specialty Generics 738.7 718.9 869.6 Net Sales $ 3,162.5 $ 3,215.6 $ 3,221.6 (1) Amitiza net sales consist of both product and royalty net sales. Refer to Note 4 for further details on Amitiza's revenues. (2) In November 2019, the Company completed the sale of BioVectra. Refer to Note 5 for further details. Selected information by geographic area was as follows: Fiscal Year 2019 2018 2017 Net sales (1) : U.S. $ 2,765.6 $ 2,834.5 $ 2,899.0 Europe, Middle East and Africa 281.8 256.8 242.3 Other 115.1 124.3 80.3 $ 3,162.5 $ 3,215.6 $ 3,221.6 Long-lived assets (2) : U.S. $ 734.3 $ 770.7 Europe, Middle East and Africa (3) 169.9 146.7 Other 4.8 76.8 $ 909.0 $ 994.2 (1) Net sales are attributed to regions based on the location of the entity that records the transaction, none of which relate to the country of Ireland. (2) Long-lived assets are primarily composed of property, plant and equipment, net. (3) Includes long-lived assets located in Ireland of $168.4 million and $145.2 million as of December 27, 2019 and December 28, 2018 , respectively.