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SEGMENT AND GEOGRAPHICAL INFORMATION - Statement of Operations (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 30, 2022 | Sep. 30, 2022 | Jul. 01, 2022 | Apr. 01, 2022 | Dec. 31, 2021 | Oct. 01, 2021 | Jul. 02, 2021 | Apr. 02, 2021 | Dec. 30, 2022 | Dec. 31, 2021 | Jan. 01, 2021
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Contract revenue | $ 113,256 | $ 121,399 | $ 102,645 | $ 91,838 | $ 92,218 | $ 98,297 | $ 84,154 | $ 79,086 | $ 429,138 | $ 353,755 | $ 390,980
Depreciation and amortization |  |  |  |  |  |  |  |  | 17,489 | 17,146 | 18,743
Interest expense, net |  |  |  |  |  |  |  |  | 5,328 | 3,869 | 5,068
Segment profit (loss) before income tax expense |  |  |  |  |  |  |  |  | (11,452) | (12,404) | (19,669)
Income tax expense (benefit) | 2,584 | (1,526) | (1,673) | (2,389) | 1,370 | (236) | (3,663) | (1,458) | (3,004) | (3,987) | (5,173)
Net income (loss) | $ (425) | $ 76 | $ (4,326) | $ (3,773) | $ (890) | $ 840 | $ (4,601) | $ (3,766) | (8,448) | (8,417) | (14,496)
Energy |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Contract revenue |  |  |  |  |  |  |  |  | 357,460 | 286,384 | 324,178
Depreciation and amortization |  |  |  |  |  |  |  |  | 16,507 | 16,156 | 17,666
Engineering and Consulting |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Contract revenue |  |  |  |  |  |  |  |  | 71,678 | 67,371 | 66,802
Depreciation and amortization |  |  |  |  |  |  |  |  | 982 | 990 | 1,077
Operating Segments | Energy |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Interest expense, net |  |  |  |  |  |  |  |  | 11 | 8 | 32
Segment profit (loss) before income tax expense |  |  |  |  |  |  |  |  | (9,544) | (4,808) | (9,963)
Income tax expense (benefit) |  |  |  |  |  |  |  |  | (2,504) | (1,546) | (2,621)
Net income (loss) |  |  |  |  |  |  |  |  | (7,041) | (3,263) | (7,343)
Operating Segments | Engineering and Consulting |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Segment profit (loss) before income tax expense |  |  |  |  |  |  |  |  | 10,896 | 9,135 | 9,500
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 2,858 | 2,936 | 2,499
Net income (loss) |  |  |  |  |  |  |  |  | 8,037 | 6,198 | 7,002
Corporate, Non-Segment |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Interest expense, net |  |  |  |  |  |  |  |  | 5,317 | 3,861 | 5,036
Segment profit (loss) before income tax expense |  |  |  |  |  |  |  |  | (12,804) | (16,731) | (19,206)
Income tax expense (benefit) |  |  |  |  |  |  |  |  | (3,358) | (5,377) | (5,051)
Net income (loss) |  |  |  |  |  |  |  |  | (9,444) | (11,352) | (14,155)
Intersegment Eliminations |  |  |  |  |  |  |  |  |  |  |
Segment reconciliation |  |  |  |  |  |  |  |  |  |  |
Contract revenue |  |  |  |  |  |  |  |  | $ 0 | $ 0 | $ 0

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