Charles Griffith
Analyst · Patrick White
Thank you, Michael. So revenues totaled $6.2 million in Q4 2021 compared to $4.2 million generated in Q4 2020. So an actual increase of 48%. This increase was due primarily to the increase in sales for armor and hermetic packages in the fourth quarter of 2021 as well as the impact of COVID-19 -- of the COVID-19 pandemic on sales in the fourth quarter of 2020.
Gross margin in Q4 '21 totaled $1.4 million or 22% of sales. This compares with gross margin in Q4 '20 of $0.5 million at 12% of sales. This increase in margin dollars directly correlates to the increase in revenue between the 2 periods. Selling, general and administrative expenses totaled $1.0 million in Q4 '21 compared with SG&A expenses of $789,000 in Q4 2020. This increase was due to the increase in sales employees, total compensation expense and to an increase in commission expense due to the higher sales volume.
The company experienced operating income of $312,000 in Q4 '21 compared to an operating loss of $291,000 in Q4 2020. This increase in operating income is due primarily to the increase in revenue, as we previously discussed. For the year ended December 25, '21, revenues totaled $22.4 million compared to $20.9 million in 2020, an increase of 8%. This increase was due primarily to the increase in sales for armor and hermetic packages in 2021.
Gross margin in 2021 totaled $4.8 million or 21% of sales, this compares with gross margin in 2020 of $4.2 million, which was 20% of sales. The increase in margin dollars is directly correlated to the increase in revenue. Selling, general and administrative expenses totaled $4.3 million in 2021. This compares to SG&A expenses of $3.3 million in 2020.
Several factors contributed to this increase. The company incurred an expense of an excess of $300,000 for onetime restructuring costs in 2021, the company paid the salaries and benefits for both our retired CEO and our new CEO during the first half of '21, they were both here at the same time, adding about $100,000 to our SG&A expenses. And we also added 3 new sales positions in 2021, which contribute to our overall increase in compensation.
The company experienced operating income of $513,000 in 2021 compared to operating income of $914,000 in 2020, and the decrease was due primarily to the increase in SG&A expenses as we previously discussed. The company recorded net income of $3.2 million in 2021 compared to $900,000 in 2020, and this increase is primarily due to the reversal of the company's deferred tax reserve.
In December of 2018, the company set up a valuation reserve against its deferred tax asset. At that time, following a period of sustained losses, management determined that it was more likely than not that this tax asset would not be used. Management has reevaluated this decision in light of recent profitability and expected future profitability and has determined that it is more likely than not that the company will be able to fully utilize this tax asset. As such, a tax benefit of $2.7 million has been recorded on the income statement as of December 25, 2021.
Turning to the balance sheet. We ended the quarter with $5 million of cash. This is an improvement to our cash position of $195,000 at the end of 2020. In May, we completed our at-the-market filing and began raising funds over that program. Through the end of the year, we raised approximately $3.4 million net under the ATM offering. These funds have enabled us to completely cease borrowing under our bank line of credit.
In addition, we have been able to absorb the increases in accounts receivable as our sales grow and in inventory as we develop our armor line. Our raise under this offering is being managed such that we've covered our short-term cash needs. We've become more selective regarding the days and market prices at which we will sell additional shares. As such, no additional cash was raised during the fourth quarter under the ATM program.
Accounts receivable at December 25, 2021, totaled $4.9 million compared with $2.9 million at the end of December 26, 2020. Our days sales outstanding totaled 72 days at the end of the quarter compared to 62 days for the prior year. This increase was due to the inclusion of about $600,000 of deferred revenue in the 2021 year-end accounts receivable. If we take that amount out, then the days sales outstanding at the end of 2021 would have been 63 days, which is in line with previous years.
Inventories totaled $3.9 million at the end of December compared -- 2021 compared with $3.7 million at the end of December 2020. This increase in inventory is due to increased armor materials offset by better management of inventory in other product lines. Improved inventory management is now an area of focus. The inventory turnover in the most recent 4 quarters was 4.7x compared to 4.5x for the period ended December 26, 2020.
Turning to the liability side. Payables and accruals totaled $2.8 million at December 25, 2021, up from $1.8 million at December 26, 2020. This is due to greater expenditures resulting from higher sales levels as well as the accrued restructuring charges, which we had previously discussed.
So for further discussion, I'd like to turn the call back over to Michael. You're on.