You are given a text that consists of multiple sentences. Your task is to perform abstractive summarization on this text. Use your understanding of the content to express the main ideas and crucial details in a shorter, coherent, and natural sounding text. 
Text: Then Tom Dineen, our chief financial officer, will give an overview of the fourth quarter and 2021 financial results, and then I will discuss our operations and the state of the market.
Copies of these documents may be obtained by contacting the company or the SEC or on the company website at ruger.com/corporate or, of course, at the SEC website at sec.gov.
We do reference non-GAAP EBITDA.
Now Tom will discuss the company's 2021 results.
For 2021, net sales were $730.7 million and diluted earnings were $8.78 per share.
For 2020, net sales were $568.9 million and diluted earnings were $5.09 per share.
The substantial increase in profitability in 2021 compared to 2020 is attributable to the increase in sales and production, the resulting favorable leveraging of fixed costs, including depreciation, engineering, and other indirect labor expenses, reduced sales promotional activities, and increased labor, and other manufacturing efficiencies.
For the fourth quarter of 2021, net sales are $168.0 million and diluted earnings were $2.14 per share.
For the corresponding period in 2020, net sales were $169.3 million and diluted earnings per $1.78 per share.
Diluted earnings per share in the fourth quarter of 2021 were increased by $0.18 due to a reduction in the effective tax rate for the year, which was recognized in the quarter.
T-bills, total $221 million.
Our current ratio was 4.3 to one, and we had no debt.
Our cash laden, debt-free balance sheet will allow us to pursue acquisitions and other capital opportunities that may emerge.
At December 31, 2021, stockholders equity was $363.7 million, which equates to a book value of $20.67 per share, of which $12.56 per share was cash and short-term investments.
In 2021, we generated $172 million dollars of cash from operations.
We reinvested $29 million of that back into the company in the form of capital expenditures, primarily related to new products.
We estimate that 2022 capital expenditures will be approximately $20 million, predominantly related to new product development.
Our ability to shift manufacturing equipment between cells and between facilities improves overall utilization and allows for reduced capital investment.
In 2021, we returned $59 million to our shareholders through the payment of dividends.
Our board of directors declared an $0.86 per share quarterly dividend for shareholders of record as of March 11, 2022, payable on March 25, 2022.
As a reminder, our quarterly dividend is approximately 40% of net income and therefore, varies quarter to quarter.
That's the financial update for 2021.
2021 was a great year for Ruger.
We ended the year with virtually no finished goods inventory, so all the firearms sold in 2021 had to be manufactured in 2021.
Our 28% increase in sales would not have been possible without the 30% increase in production at our factories.
And this 30% increase was achieved with a manpower increase of less than 10%.
The manufacturing efficiency gains drove a 109% return on net operating assets for the year, which is a remarkable feat.
Our dedicated workforce accomplish this despite the highly publicized challenges of tight labor markets, transportation, and supply chain issues, and COVID-19 obstacles that we experienced throughout the year.
Following a 44% increase in 2020, the sell-through of our products from distributors to retailers increased again in 2021, this time by 4% despite the 12% reduction in the National Instant Criminal Background Check System background checks as suggested by the National Shooting Sports Foundation.
The increase in the sell-through of our products compared favorably to the decrease in adjusted NICS background checks in 2021 and may be attributable to strong consumer demand for our products, increased availability of our products at the distributors and at retail as a result of our increased production, and the introduction of popular new products.
Led by the award-winning Ruger-5.7 pistol, the MAX-9, and the LCP MAX pistol, our new product sales in 2021 represented $155 million, or 22% of firearm sales, an increase of $45 million from $111 million, or 22% of firearm sales in 2020.
As a reminder, derivatives in product line extensions of mature product families are not included in our new products sales calculations.
We ended 2021 on a high note as we shipped the first Ruger-made Marlin lever action rifles.
The model 1895 SBL, chambered in 45-70 government in December.
During the past year, our team completed a thorough design and production review of the 1895 focused on ensuring the highest quality, accuracy, and performance standards.
Being a longtime Marlin fan, I knew that we needed to take our time and make sure that our reintroduction was nothing short of perfect.
From the quality of the firearm to clear ways for consumers to differentiate Ruger-made Marlins, we focused on getting every detail right.
I look forward to reintroducing many more Marlins in 2022 and in the years to come.
Long live the lever gun.
Our finished goods inventory remains significantly below pre-COVID-19 pandemic levels.
Distributor inventories of our products increased 125,000 units in 2021, but remained below the level needed to support rapid fulfillment of retailer demand for most products.
We have an expansive product line, which ranges from our versatile pistols to bolt-action hunting rifles, to our classic revolvers to Marlin lever action rifles.
This provides some stability in the volatile firearms market as we can reallocate our labor and machinery to prioritize the manufacture of products that are in strong demand while we replenish our inventories of models that appear to be in adequate supply in the distribution channel.
Our ability to reallocate resources and our willingness to maintain appropriate levels of inventory strengthen us as demand ebbs and flows within the various diverse sectors of the industry.
I'm excited as we enter 2022.
We will remain disciplined and committed to our strategy of pursuing manufacturing excellence and vigorously developing innovative and exciting new products.
We look forward to watching some of these new products under both the Ruger and Marlin brands in 2022.
Those are the highlights of 2021.
Operator, may we have the first question?

user
compname reports 2021 diluted earnings of $8.78 per share.
compname reports 2021 diluted earnings of $8.78 per share and declares dividend of 86¢ per share.
q4 earnings per share $2.14.

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