Revenue
The increase in revenue of approximately $2,759,000, or 31%, for the three-month period ended September 30, 2023 and is due primarily to increased volume, as units shipped were 29% higher than the three-month period ending September 30, 2022. This is directly attributable to concerted efforts made to increase production output given the strong customer demand and existing backlog. The revenue increase of $4,552,000, or 17%, for the nine-month period ended September 30, 2023 when compared to the same period in 2022, is primarily attributable to higher volumes, as units shipped have increased 16% over that time period. The post-COVID recovery and ramp up of the commercial aircraft industry, which our customers’ systems directly support, continues to be very strong as evidenced by customer forecasts for 2024.
The sequential revenue growth in 2023 was anticipated and is expected to continue based on our focus on production output and commitment to reducing product flow constraints to achieve the revenue growth targets.
Gross Profit/Margin
Gross Profit increased approximately $1,272,000, or 104%, for the three-month period ended September 30, 2023 when compared to the same period in 2022. The Gross Margin of 21.6% for the quarter ended September 30, 2023 was 7.7 percentage points higher than the margin of 13.9% for the same period in 2022. Gross profit benefited from the increased sales volumes, resulting in favorable production variances and lower overhead costs, partially offset by product liability costs of $500,000 recorded for a specific customer claim during the third quarter, when compared to the same period in 2022.
Gross profit increased approximately $114,000, or 2%, for the nine-month period ended September 30, 2023 when compared to the same period in 2022. The gross margin of 16.1% for the nine-months ended September 30, 2023 was 2.3 percentage points lower than the margin of 18.4% for the same period in 2022. Although gross profit in 2023 benefited from the increased sales volumes, it was more than offset by the higher manufacturing costs driven by increased labor and material costs, when compared to the same period in 2022.
As previously noted, research and development (R&D) and certain insurance expenditures were reclassified from cost of goods sold to selling, general and administrative (SG&A) expenses, effective January 1, 2023. For the three- and nine-month periods ended September 30, 2023, the reclassifications were approximately $568,000 and $1,470,000, respectively, as compared to the reclassified amounts of approximately $377,000 and $1,029,000, respectively, for the same periods in 2022. There was no impact to the Condensed Consolidated Statement of Operations due to the reclassification.
Selling, General and Administrative Expenses
Selling, general and administrative expenses (SG&A) for the three-month period ended September 30, 2023 of $2,219,000 increased approximately $301,000, or 16%, when compared to SG&A expenses of $1,918,000 during the same period in 2022. This increase is primarily attributable to increased sales & marketing personnel costs and higher R&D costs attributable to projects focused on expanding the product portfolio, partially offset by insurance proceeds and legal expense recovery related to litigation, that did not occur during the same period in 2022.
SG&A for the nine-month period ended September 30, 2023 of $7,663,000 increased approximately $1,744,000, or 29%, when compared to SG&A expenses of $5,919,000 during the same period in 2022. This increase is primarily due to significant, non-recurring expenses of approximately $1,211,000, increased sales & marketing personnel costs and higher R&D costs attributable to projects focused on expanding the product portfolio, that did not occur during the same period in 2022.