For the second quarter of 2021, net sales were $200.1 million and diluted earnings were $2.50 per share.
For the comparable prior year period, net sales were $130.3 million and diluted earnings were $1.05 per share.
For the first six months of 2021, net sales were $384.4 million and diluted earnings were $4.66 per share.
For the corresponding period in 2020, net sales were $253.9 million and diluted earnings were $1.91 per share.
During the first half of 2021, we generated $76.2 million of cash from operations.
We reinvested $11.5 million of that back into the company in the form of capital expenditures.
We estimate that 2021 capital expenditures will be approximately $20 million predominantly related to new product development.
Our cash and short-term investments, which are invested in UST bills, totaled $173.6 million.
Our current ratio was 3.7:1, and we had no debt.
Our stockholders' equity was $319.1 million, which equates to a book value of $18.14 per share, of which $9.86 per share was cash and short-term investments.
In the first month -- in the first six months of 2021, we returned $27.6 million to our shareholders through the payment of dividends.
Our Board of Directors declared a $1 per share quarterly dividend for shareholders of record as of August 16, 2021, payable on August 27, 2021.
Upon receiving the $1 quarterly dividend, shareholders will have received over $2.50 of dividends per share thus far in 2021.
As a reminder, our quarterly dividend is approximately 40% of net income and, therefore, varies quarter-to-quarter.
The estimated unit sell-through of the company's products from the independent distributors to retailers increased 13% in the first half of '21 compared to the prior year period.
For the same period, the National Instant Criminal Background Check System background checks, as adjusted by the National Shooting Sports Foundation, commonly referred to as NICS checks, decreased 5%.
On the heels of the successful MAX-9 pistol launch earlier this year, we introduced the Ruger LCP MAX, a 380 Auto pistol in June.
These include the extremely popular Ruger-57 Pistol, which is awarded the 2020 Caliber Award for best overall new product by the Professional Outdoor Media Association in conjunction with the NASGW.
22 Long rifle, which is based on the venerable LCP platforms and utilizes our Lite Rack system for easier slide manipulation and reduced recoil.
The Wrangler revolver, our latest take on the classic single-action revolver, which shows no signs of slowing down and the MAX-9 pistol, a versatile 9-millimeter pistol that has been met with tremendous excitement.
In the first half of 2021, new product sales represented $78 million or 22% of firearm sales compared to $48 million or 21% of firearm sales in the first half of 2020.
Since March of 2020, our workforce has been strengthened by approximately 400 folks, an increase of 25%, and our quarterly unit production has increased by over 200,000 units or 58%.
And despite the growth in our output at the end of the second quarter of 2021, our finished goods inventory and distributor inventories of Ruger products were 160,000 units lower than they were at the end of the first quarter of 2020.
We estimate that COVID-related costs will total approximately $1.5 million in 2021.
Included in this estimate is a $200 bonus for every employee who becomes fully vaccinated.

Summary:
For the second quarter of 2021, net sales were $200.1 million and diluted earnings were $2.50 per share.
Upon receiving the $1 quarterly dividend, shareholders will have received over $2.50 of dividends per share thus far in 2021.