Total engineering, comprised of company, customer and partner-funded and nonrecurring engineering costs, decreased compared to prior year in line with the changes in the commercial environment. For the year ended December 31, 2020, company-funded research and development spend decreased compared to 2019, and we expect the reduction to continue in line with the actions outlined above. However, customer and partner-funded engineering efforts, primarily in our Military business, increased compared to the prior year. In September 2020, Aviation announced it received certification from the FAA for the GE9X engine, the world’s largest and most powerful commercial aircraft engine. Aviation is taking actions to protect its ability to serve its customers now and as the global airline industry recovers. While its near-term focus remains on navigating the COVID-19 pandemic, Aviation’s deep history of innovation and technology leadership, commercial engine installed base of approximately 37,700 units, military engine installed base of approximately 26,500 units, with approximately 12,500 units under long-term service agreements, and $260 billion backlog represents strong long-term fundamentals. Aviation is taking actions to protect and strengthen its business and seeks to emerge from this crisis stronger and drive long-term cash and profitable growth over time. (a) LEAP engines are a subset of Commercial Engines (b) Commercial externally shipped spares and spares used in time & material shop visits in millions of dollars per day. Backlog as of December 31, 2020 decreased $12.8 billion (5%) from December 31, 2019, primarily due to a reduction in our Commercial Services backlog and cancellations of commercial equipment orders, which included approximately 1,500 LEAP 1-B unit order cancellations and 22 GE9x unit order cancellations. The reduction to Commercial Services backlog reflects estimates of lower engine utilization, the partial cancellation of long-term service agreements related to the equipment unit order cancellations, and anticipated customer fleet restructuring and contract modifications. Backlog adjustments could be necessary in future periods for additional cancellations of new commercial engine orders, fleet retirements, or changes to customer aircraft utilization and operating behavior. For the year ended December 31, 2020, segment orders were down $15.1 billion (41%), segment revenues were down $10.8 billion (33%) and segment profit was down $5.6 billion (82%). (a) Aviation segment revenues represent 30% and 27% of total industrial revenues and total segment revenues, respectively, for the year ended December 31, 2020. (b) Aviation segment profit represents 17% of total industrial profit for the year ended December 31, 2020. (c) Included restructuring charges of $26 million, $8 million and $12 million for the years ended December 31, 2020, 2019 and 2018, respectively, that were previously reported within the Corporate segment and were reclassified into the Aviation segment results in the fourth quarter of 2020 for all periods presented. For a summary of all restructuring charges by segment, see the Other Consolidated Information section. 2020 2019 2018 Equipment $ 34,486  $ 39,131  $ 37,831  Services 225,927  234,114  185,696  Total backlog $ 260,412  $ 273,245  $ 223,527  Equipment $ 8,119  $ 14,459  $ 15,268  Services 13,471  22,280  20,248  Total orders $ 21,590  $ 36,738  $ 35,517  Commercial Engines & Services $ 13,017  $ 24,217  $ 22,724  Military 4,572  4,389  4,103  Systems & Other 4,453  4,269  3,740  Total segment revenues $ 22,042  $ 32,875  $ 30,566  Equipment $ 8,582  $ 12,737  $ 11,499  Services 13,460  20,138  19,067  Total segment revenues(a) $ 22,042  $ 32,875  $ 30,566  Segment profit (loss)(b)(c) $ 1,229  $ 6,812  $ 6,454  Segment profit margin 5.6 % 20.7 % 21.1 % Orders Sales (In units, except where noted) 2020 2019 2020 2019 Commercial Engines 678  2,390  1,487  2,863  LEAP Engines(a) 351  1,568  815  1,736  Military Engines 1,023  801  683  717  Spares Rate(b) $ 18.0 $ 31.0  GE 2020 FORM 10-K  15