I'm incredibly proud of ResMedians across our global teams, many of whom are working 24/7 to get our products and solutions into the hands of patients who need them most.
2 market share position, announced a recall mid-June that has created unprecedented dislocations in the market.
1 market share position and also trying to meet as much of the No.
2 market share position as possible around the world.
We have an incredible Six Sigma Black Belt laden team of supply chain specialists working on these issues 24/7.
1 priority will always be patients, doing our best to help those who need treatment for sleep apnea, for COPD, for the asthma and for other chronic respiratory diseases as well as critical out-of-hospital care.
We are still seeing a divergence in total patient flow and sleep lab capacity from 75% to 95% of pre-COVID levels in some countries, up to 100% plus of pre-COVID levels in others.
In August, we launched our next-generation device platform that we call AirSense 11 into the United States market.
We will be introducing the AirSense 11 into additional countries very soon.
Globally, we continue to sell our market-leading legacy platform, the AirSense 10, to be able to maximize the total volume of CPAP, APAP, and bi-levels available for customers.
Clearly, the ongoing adoption of both the AirSense 10 and the AirSense 11 platforms remains very, very strong.
It's still early into the SirSense 11 launch but initial customer feedback, combined with the detailed responses to our controlled product launch, tells me that the AirSense 11 is also another success for ResMed.
I was able to attend the California Sleep Society meeting in person actually during the quarter, and I was able to observe this firsthand the responses to the latest innovations on the AirSense 11, such as personal therapy assistant, care check-in, and the incredible rate of uptake of the patient-centric app called myAir, which has been upgraded for AirSense 11.
And the uptake on that is almost double what it was for the myAir app than AirSense 10.
What's clear to me is that this platform, the AirSense 11, benefits not only patients and their bed partners.
As a two-way digital health comms platform with many technical features of -- that represent significant therapeutic advances, AirSense 11 is not only easy to set up and use, it also offers a very rich patient-centric experience.
All AirSense 11 devices are 100% cloud connectable with upgraded digital health technology that is able to increase patient adherence to improve clinical outcomes and to deliver proven cost reductions within healthcare providers and physician's own health systems.
With 936 million sleep apnea sufferers worldwide, this work is critical to our mission.
Let me now turn to a discussion of our respiratory care business, focusing on our strategy to better serve the 380 million COPD patients and the 330 million asthma patients worldwide.
With over 10 billion nights now, 10 billion nights of medical data in the cloud and over 15.5 million, 100% cloud connectable medical devices on bedside tables in 140 countries worldwide, we are unlocking value from these data to help patients, providers, physicians, payers, and entire healthcare systems.
Our mission and goal to improve 250 million lives through better healthcare in 2025, drives and motivates me and ResMedians every day.
You, our ResMed team, have helped save the lives of many hundreds if not thousands of people around the world with COVID-19 with those emergency needs these last 18 months.
Group revenue for the September quarter was $904 million, an increase of 20%.
In constant currency terms, revenue increased by 19%.
In the September quarter, we estimate the incremental revenue from COVID-19-related demand was approximately $4 million, compared to $40 million estimated incremental revenue from the COVID-19-related demand in the prior year quarter.
And excluding the impact of COVID-19-related revenue in both the September 2021 and September 2020 quarters, our global revenue increased by 25% on a constant currency basis.
In relation to the impact of our competitors' recall, we estimate that we generated incremental device revenue in the range of $80 million to $90 million in the September quarter.
So, taking a look at our geographic revenue distribution and excluding revenue from our Software-as-a-Service business, our sales in U.S., Canada and Latin America countries were $491 million, an increase of 22%.
Sales in Europe, Asia, and other markets totaled $315 million, an increase of 23% and or an increase of 21% in constant currency terms.
By product segment, U.S., Canada and Latin America device sales were $276 million, an increase of 40%.
Masks and then other sales were $215 million, an increase of 5%.
In Europe, Asia and other markets, device sales totaled $218 million, an increase of 24% or in constant currency terms, a 22% increase.
Masks and other sales in Europe, Asia, and other markets were $97 million, an increase of 21%, or in constant currency terms, an 18% increase.
Globally, in constant currency terms, device sales increased by 31% while masks and other sales increased by 8%.
Excluding the impact of COVID-19-related sales in both the current quarter and the prior year quarter, global device sales increased by 44% in constant currency terms while masks and other sales increased by 10% in constant currency terms.
Software-as-a-Service revenue for the September quarter was $98 million, an increase of 6% over the prior year quarter.
For the balance of fiscal year '22, we expect several factors will drive demand, including the general recovery of the global sleep market from COVID-19 impacts, the ongoing launch of our next-generation AirSense 11 platform into markets and geographies, and share gains during our competitors' recall.
Based on the latest information available, we continue to expect component supply constraints will limit the incremental device revenue resulting from competitor's recall to somewhere between $300 million and $350 million for fiscal year 2022.
Our non-GAAP gross margin decreased by 270 basis points to 57.2% in the September quarter, compared to 59.9% here in the same quarter last year.
Our SG&A expenses for the first quarter were $177 million, an increase of 11%, or in constant currency terms, SG&A expenses increased by 10% compared to the prior year period.
SG&A expenses as a percentage of revenue have improved to 19.5%, compared to the 21.1% we reported in the prior year quarter.
Looking forward and subject to currency movements, we expect SG&A as a percentage of revenue to be in the range of 20% to 22% for this balance of the fiscal year '22.
R&D expenses for the quarter were $60 million, an increase of 10%, or on a constant currency basis, an increase of 9%.
R&D expenses as a percentage of revenue was 6.6%, compared to 7.3% in the prior year quarter.
Looking forward and subject to currency movements, we expect R&D expenses as a percentage of revenue to be in the vicinity of 7% for the balance of fiscal year '22.
Total amortization of acquired intangibles was $19 million for the quarter, and stock-based compensation expense for the quarter was around $17 million.
Our non-GAAP operating profit for the quarter was $281 million, an increase of 18%, underpinned by strong revenue growth.
During the quarter, we finalized the deed of settlement with the Australian Taxation Office, or ATO, covering transit pricing audits for the years 2009 through 2018, and also agreed on transfer pricing principles for the future.
And in anticipation of this settlement, we had previously estimated and recorded an accounting tax reserve of $249 million, net of credits and deductions in our FY '21 financial results.
In relation to the conclusion of the settlement in the current quarter, we recorded an additional GAAP tax expense of $4 million associated with lower tax credits, which were driven by foreign currency movements.
So, on a GAAP basis, our effective tax rate for the September quarter was 21.3% while on a non-GAAP basis, our effective tax rate for the quarter was 20%.
Looking forward, we estimate our non-GAAP effective tax rate for the fiscal year '22 will be in the range of 19% to 20%.
Non-GAAP net income for the quarter was $222 million, and an increase of 20%.
Non-GAAP diluted earnings per share for the quarter were $1.51, an increase of 19%.
Our GAAP net income for the quarter was $204 million, and our GAAP diluted earnings per share for the quarter was $1.39.
We had negative cash flow from operations for the quarter of $66 million due to the payment of about $285 million to the Australian Taxation Office associated with the deed of settlement.
After adjusting for this payment, our operating cash flow for the quarter was $219 million, reflecting robust underlying earnings, partially offset by increases in working capital.
Capital expenditure for the quarter was $27 million.
Depreciation and amortization for the quarter September totaled $39 million.
During the quarter, we paid dividends of $61.2 million.
We recorded equity losses of $1.4 million in our income statement in the September quarter associated with the Primasun joint venture with Verily.
We expect to then report equity losses of approximately $2 million per quarter through the balance of fiscal year '22 associated with the joint venture operations.
We ended the first quarter with a cash balance of $276 million.
At September 30, we had $806 million of gross debt and $530 million in net debt.
Our debt levels remained modest, and at September 30, we had almost $1.5 billion available for drawdown under our existing revolver facility.
Our board of directors today declare our quarterly dividend of $0.42 per share, reflecting the board's confidence in our operating performance.

Summary:
Group revenue for the September quarter was $904 million, an increase of 20%.
Non-GAAP diluted earnings per share for the quarter were $1.51, an increase of 19%.
Our GAAP net income for the quarter was $204 million, and our GAAP diluted earnings per share for the quarter was $1.39.