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SEGMENT AND GEOGRAPHICAL INFORMATION - Statement of Operations (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 29, 2023 | Sep. 29, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 30, 2022 | Sep. 30, 2022 | Jul. 01, 2022 | Apr. 01, 2022 | Dec. 29, 2023 | Dec. 30, 2022 | Dec. 31, 2021
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Contract revenue | $ 155,677 | $ 132,738 | $ 119,077 | $ 102,603 | $ 113,256 | $ 121,399 | $ 102,645 | $ 91,838 | $ 510,095 | $ 429,138 | $ 353,755
Depreciation and amortization |  |  |  |  |  |  |  |  | 16,431 | 17,489 | 17,146
Interest expense, net |  |  |  |  |  |  |  |  | 9,413 | 5,328 | 3,869
Segment profit (loss) before income tax expense |  |  |  |  |  |  |  |  | 14,591 | (11,452) | (12,404)
Income tax (benefit) expense | 1,953 | 713 | 243 | 756 | 2,584 | (1,526) | (1,673) | (2,389) | 3,665 | (3,004) | (3,987)
Net Income (Loss) | $ 8,031 | $ 1,566 | $ 397 | $ 932 | $ (425) | $ 76 | $ (4,326) | $ (3,773) | 10,926 | (8,448) | (8,417)
Energy |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Contract revenue |  |  |  |  |  |  |  |  | 426,976 | 357,460 | 286,384
Depreciation and amortization |  |  |  |  |  |  |  |  | 15,176 | 16,507 | 16,156
Engineering and Consulting |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Contract revenue |  |  |  |  |  |  |  |  | 83,119 | 71,678 | 67,371
Depreciation and amortization |  |  |  |  |  |  |  |  | 1,255 | 982 | 990
Operating Segments | Energy |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Interest expense, net |  |  |  |  |  |  |  |  | 6 | 11 | 8
Segment profit (loss) before income tax expense |  |  |  |  |  |  |  |  | 16,921 | (9,544) | (4,808)
Income tax (benefit) expense |  |  |  |  |  |  |  |  | 4,250 | (2,504) | (1,546)
Net Income (Loss) |  |  |  |  |  |  |  |  | 12,671 | (7,041) | (3,263)
Operating Segments | Engineering and Consulting |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Segment profit (loss) before income tax expense |  |  |  |  |  |  |  |  | 10,270 | 10,896 | 9,135
Income tax (benefit) expense |  |  |  |  |  |  |  |  | 2,580 | 2,858 | 2,936
Net Income (Loss) |  |  |  |  |  |  |  |  | 7,690 | 8,037 | 6,198
Corporate, Non-Segment |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Interest expense, net |  |  |  |  |  |  |  |  | 9,407 | 5,317 | 3,861
Segment profit (loss) before income tax expense |  |  |  |  |  |  |  |  | (12,600) | (12,804) | (16,731)
Income tax (benefit) expense |  |  |  |  |  |  |  |  | (3,165) | (3,358) | (5,377)
Net Income (Loss) |  |  |  |  |  |  |  |  | $ (9,435) | $ (9,444) | $ (11,352)

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