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Costs and Estimated Earnings in Excess of Billings (Tables) | 12 Months Ended
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Sep. 30, 2020
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Costs and Estimated Earnings in Excess of Billings on Uncompleted Contracts | Costs and estimated earnings in excess of billings on uncompleted contracts as of September 30, 2020 and 2019 consisted of the following:
|  | September 30, |
|  | 2020 |  |  | 2019 |
Costs incurred on uncompleted contracts |  | $ | 10,390,000 |  |  | $ | 18,707,000 |
Estimated earnings |  |  | 4,680,000 |  |  |  | 9,063,000 |
|  |  | 15,070,000 |  |  |  | 27,770,000 |
Billings to date |  |  | 8,665,000 |  |  |  | 13,932,000 |
Costs and estimated earnings in excess of billings |  | $ | 6,405,000 |  |  | $ | 13,838,000 |

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