OPERATING SEGMENTS | NOTE 13. OPERATING SEGMENTS Operating segments under GAAP are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the Chief Operating Decision Maker (CODM), or decision-making group, in deciding how to allocate resources and in assessing performance. Our CODM is the Chief Operating Officer. We use segment EBIT (defined as earnings before interest expense, income taxes and noncontrolling interests) as a primary basis for the CODM to evaluate the performance of each of our operating segments. Segment amounts exclude certain expenses not specifically identifiable to segments. As previously announced, beginning with the second quarter of 2016, we realigned certain of our reportable segments to be consistent with changes to our organizational structure and how the CODM monitors the performance of our segments. We reorganized our business to combine our Power Generation segment and our high-horsepower engine business to create the new Power Systems segment. Our reportable operating segments consist of Engine, Distribution, Components and Power Systems. We began to report results for our new reporting structure in the second quarter of 2016 and also reflected this change for historical periods. We allocate certain common costs and expenses, primarily corporate functions, among segments. These include certain costs and expenses of shared services, such as information technology, human resources, legal, finance and supply chain management. In addition to the reorganization noted above, we reevaluated the allocation of these costs, considering the new segment structure created in April 2016 and adjusted our allocation methodology accordingly. The revised methodology, which is based on a combination of relative segment sales and relative service usage levels, is effective for the periods beginning after January 1, 2016 and resulted in the revision of our segment operating results, including segment EBIT, for all four segments for the first quarter of 2016 with a greater share of costs allocated to the Distribution and Components segments than in previous years. Prior periods were not revised for the new allocation methodology. These changes had no impact on our consolidated results. Our new reporting structure is organized according to the products and markets each segment serves . The Engine segment produces engines (15 liters and less in size) and associated parts for sale to customers in on-highway and various off-highway markets. Our engines are used in trucks of all sizes, buses and recreational vehicles, as well as in various industrial applications, including construction, agriculture, power generation systems and other off-highway applications. The Distribution segment includes wholly-owned and partially-owned distributorships engaged in wholesaling engines, generator sets and service parts, as well as performing service and repair activities on our products and maintaining relationships with various OEMs throughout the world. The Components segment sells filtration products, aftertreatment systems, turbochargers and fuel systems. The Power Systems segment is an integrated power provider, which designs, manufactures and sells engines (16 liters and larger) for industrial applications (including mining, oil and gas and marine), standby and prime power generator sets, alternators and other power components. The accounting policies of our operating segments are the same as those applied in our Condensed Consolidated Financial Statements . We prepared the financial results of our operating segments on a basis that is consistent with the manner in which we internally disaggregate financial information to assist in making internal operating decisions. As noted above, we allocate certain common costs and expenses, primarily corporate functions, among segments. We do not allocate debt-related items, actuarial gains or losses, prior service costs or credits, changes in cash surrender value of corporate owned life insurance or income taxes to individual segments. Segment EBIT may not be consistent with measures used by other companies. Summarized financial information regarding our reportable operating segments for the three and nine month periods is shown in the table below: In millions Engine Distribution Components Power Systems Non-segment Items (1) Total Three months ended October 2, 2016 External sales $ 1,357 $ 1,497 $ 824 $ 509 $ — $ 4,187 Intersegment sales 502 7 319 347 (1,175 ) — Total sales 1,859 1,504 1,143 856 (1,175 ) 4,187 Depreciation and amortization (2) 42 28 32 29 — 131 Research, development and engineering expenses 56 3 54 44 — 157 Equity, royalty and interest income from investees 38 19 9 8 — 74 Loss contingency 99 (3) — — — — 99 Interest income 3 1 1 1 — 6 Segment EBIT 89 96 148 59 6 398 Three months ended September 27, 2015 External sales $ 1,627 $ 1,543 $ 891 $ 559 $ — $ 4,620 Intersegment sales 475 8 349 423 (1,255 ) — Total sales 2,102 1,551 1,240 982 (1,255 ) 4,620 Depreciation and amortization (2) 47 26 28 27 — 128 Research, development and engineering expenses 73 2 65 57 — 197 Equity, royalty and interest income from investees 33 19 9 17 — 78 Interest income 6 1 1 1 — 9 Segment EBIT 217 123 156 74 7 577 Nine months ended October 2, 2016 External sales $ 4,350 $ 4,493 $ 2,654 $ 1,509 $ — $ 13,006 Intersegment sales 1,487 18 1,005 1,076 (3,586 ) — Total sales 5,837 4,511 3,659 2,585 (3,586 ) 13,006 Depreciation and amortization (2) 121 86 95 87 — 389 Research, development and engineering expenses 166 10 161 141 — 478 Equity, royalty and interest income from investees 120 56 29 29 — 234 Loss contingency 138 (3) — — — — 138 Interest income 8 3 3 4 — 18 Segment EBIT 492 270 501 195 15 1,473 Nine months ended September 27, 2015 External sales $ 5,150 $ 4,499 $ 2,839 $ 1,856 $ — $ 14,344 Intersegment sales 1,422 23 1,097 1,225 (3,767 ) — Total sales 6,572 4,522 3,936 3,081 (3,767 ) 14,344 Depreciation and amortization (2) 140 78 82 81 — 381 Research, development and engineering expenses 195 8 183 172 — 558 Equity, royalty and interest income from investees 107 60 26 47 — 240 Interest income 10 3 3 4 — 20 Segment EBIT 695 324 574 302 (35 ) 1,860 ____________________________________ (1) Includes intersegment sales, intersegment profit in inventory eliminations and unallocated corporate expenses. There were no significant unallocated corporate expenses for the three and nine months ended October 2, 2016 and September 27, 2015 . (2) Depreciation and amortization as shown on a segment basis excludes the amortization of debt discount and deferred costs included in the Condensed Consolidated Statements of Income as "Interest expense." The amortization of debt discount and deferred costs was $2 million for the nine months ended October 2, 2016 and September 27, 2015. (3) See Note 10 , " COMMITMENTS AND CONTINGENCIES ," for additional information. A reconciliation of our segment information to the corresponding amounts in the Condensed Consolidated Statements of Income is shown in the table below: Three months ended Nine months ended In millions October 2, September 27, October 2, September 27, Total segment EBIT $ 398 $ 577 $ 1,473 $ 1,860 Less: Interest expense 16 16 51 47 Income before income taxes $ 382 $ 561 $ 1,422 $ 1,813 |