It was a successful year across EnPro as we continue to rise to the occasion to meet the challenges and opportunities that have arisen over the past 12 months.
For the year, sales grew 6.3% to $1.14 billion.
Organic sales grew 14.4%.
Adjusted EBITDA of $208.4 million, increased by 23.8% compared to 2020.
Adjusted EBITDA margin of 18.3%, increased 260 basis points, driven primarily by organic sales increases.
Further, we expect to maintain our strong recurring revenue streams with aftermarket revenue across our businesses approaching 50% of total company revenue.
As reported, sales of $280.8 million in the fourth quarter, increased 1.7% year over year.
Organic sales for the fourth quarter increased 10.4% compared to the fourth quarter of 2020.
Adjusted EBITDA of $47.7 million, decreased 0.8% compared to the prior-year period.
Corporate expenses of $26.9 million in the fourth quarter of 2021 were up from $10.6 million a year prior, driven primarily by acquisition-related expenses associated with the NxEdge transaction, as well as increased incentive compensation expenses, driven mainly by our fourth quarter share price performance.
Adjusted diluted earnings per share of $1.23 was essentially flat compared to the prior-year period.
Such amortization -- amortization of acquisition-related intangible assets in the fourth quarter was $12.7 million, compared to $10.9 million in the prior-year period, reflecting the additions of Alluxa and NxEdge.
Due to the impact of divestitures, Sealing Technology sales of $143.9 million, decreased 7% versus the prior year.
Excluding the impact of divested businesses and foreign exchange translation, sales increased 12% versus the prior-year period, driven primarily by strong demand in heavy-duty truck, aerospace, nuclear, and food and pharma markets.
Also due to businesses divested in 2020 and 2021, adjusted segment EBITDA decreased 12.3% versus the prior-year period.
Excluding the impact of divestitures and foreign exchange translation, adjusted segment EBITDA increased 3% compared to the prior-year period.
Fourth quarter sales of $69.1 million, increased 38.5% versus the prior-year period, driven by strong demand in the semiconductor market and the acquisitions of Alluxa and NxEdge.
Excluding the impact of acquisitions and foreign exchange translation, sales increased 16.6% versus the prior-year period.
For the fourth quarter, adjusted segment EBITDA increased 35.7% versus the prior-year period, driven by the acquisitions and strong organic sales growth.
Excluding the impact of the acquisitions and foreign exchange translation, adjusted segment EBITDA increased 10.4% compared to the prior-year period.
In Engineered Materials, sales decreased 7.3% versus the prior-year period, driven by the divestitures of the GGB bushing block and CPI businesses.
Fourth quarter adjusted segment EBITDA decreased 21.9% versus the prior-year period, driven by raw material inflation and supply chain headwinds, as well as the decline in automotive production in Europe and the United States.
Excluding the impact of divestitures and foreign exchange translation, adjusted segment EBITDA decreased by a comparable amount around 20.2% compared to the prior-year period.
We ended the fourth quarter with cash of $338.1 million, $310 million of which is located outside the United States.
At December 31, we had $213.6 million available for borrowing under our revolving credit facility.
Free cash flow in 2021 was $123.2 million, up from $39.3 million in the prior year, driven by higher operating profits and lower cash taxes resulting from a tax refund associated with a federal income tax audit resolution, partially offset by working capital investments supporting stronger demand.
During the fourth quarter, we paid a $0.27 per share quarterly dividend.
For the year, dividend payments totaled $22.4 million.
Our board of directors voted to increase our quarterly dividend to $0.28 per share effective with the March payment representing our 7th consecutive annual increase in our quarterly dividend since we began paying dividends in 2015.
Taking into consideration all the factors that we know at this time, we expect low double-digit revenue growth over reported 2021 sales of $1.14 billion and we expect adjusted EBITDA to be in the range of $263 million to $275 million, implying adjusted EBITDA margins north of 20%.
Further, we expect adjusted diluted earnings per share from continuing operations to be in the range of $6.70 to $7.25 using a normalized 27% tax rate, reduced from 30% last year.
The reduction in our normalized tax rate assumption for 2022 results from the portfolio actions completed late in 2021 which tilt our portfolio to a higher portion of earnings in the United States.
Our guidance assumes depreciation and amortization expense, excluding amortization of acquisition-related intangible assets of $37 million to $39 million and net interest expense of $30 million to $33 million.
Our 2022 guidance implies adjusted EBITDA margins around 21%, up from the 14% in 2019 when we first began our portfolio reshaping strategy.

Summary:
As reported, sales of $280.8 million in the fourth quarter, increased 1.7% year over year.
Adjusted diluted earnings per share of $1.23 was essentially flat compared to the prior-year period.
Taking into consideration all the factors that we know at this time, we expect low double-digit revenue growth over reported 2021 sales of $1.14 billion and we expect adjusted EBITDA to be in the range of $263 million to $275 million, implying adjusted EBITDA margins north of 20%.
Further, we expect adjusted diluted earnings per share from continuing operations to be in the range of $6.70 to $7.25 using a normalized 27% tax rate, reduced from 30% last year.
The reduction in our normalized tax rate assumption for 2022 results from the portfolio actions completed late in 2021 which tilt our portfolio to a higher portion of earnings in the United States.