Since this COVID-19 pandemic began in January, ResMed has produced hundreds of thousands of ventilators, providing the gift of breath to people in need in 140 countries worldwide.
We have seen a steady sequential, what we would call U-shape recovery of patient flow to primary care physicians as well as then to specialist physicians across the 140 countries that we serve.
This is just as we forecast 90 days ago on our Q4 earnings call.
During the first quarter of fiscal year 2021, we generated over $144 million of cash, allowing us to return $57 million of cash as dividends to our shareholders.
We have a very full pipeline of innovative solutions that will generate both medium and long-term value for customers with an industry-leading intellectual property portfolio of over 6,000 patents and designs.
We now have over 7 billion nights of respiratory medical data in our cloud-based Air Solutions platform.
We've provided over 12.5 million 100% cloud-connectable medical devices to customers.
And we have over 14 million patients enrolled in our AirView software solution.
These three trends: one, the increased importance of respiratory medicine; two, the increased importance of digital health; and three, the increased importance of out-of-hospital healthcare, will all help ResMed meet and beat our goal of growing volume at double digits from 2020 through 2025 and improving over 250 million lives by 2025.
Group revenue for the September quarter was $752 million, an increase of 10% over the prior-year quarter.
In constant currency terms, revenue increased by 9% compared to the prior year quarter.
We estimate that the incremental revenue benefit from ventilator devices and related accessories derived from COVID-19 demand was approximately $40 million in the first quarter.
Taking a closer look at our geographic distribution, and excluding revenue from our Software as a Service business, our sales in U.S., Canada, and Latin America countries were $403 million, an increase of 9% over the prior-year quarter.
Sales in Europe, Asia and other markets totaled $257 million, an increase of 15% over the prior-year quarter or an increase of 10% in constant currency terms.
By product segment, U.S., Canada, and Latin America device sales were $197 million, an increase of 6% over the prior-year quarter.
Masks and other sales were $206 million, an increase of 12% over the prior-year quarter.
In Europe, Asia and other markets, device sales totaled $176 million, an increase of 16% over the prior-year quarter or in constant currency terms, an 11% increase.
Masks and other sales in Europe, Asia, and other markets were $81 million, an increase of 12% over the prior-year quarter or in constant currency terms, an increase of 8%.
Globally, in constant currency terms, device sales increased by 8%, while masks and other sales increased by 11% over the prior-year quarter.
Software as a Service revenue for the first quarter was $92 million, an increase of 6% over the prior-year quarter.
On a non-GAAP basis, SaaS revenue increased by 4%.
Our non-GAAP gross margin improved by 30 basis points to 59.9% in the September quarter compared to 59.6% in the same quarter last year.
Our SG&A expenses for the first quarter were $159 million, a decrease of 5% over the prior-year quarter, or in constant currency terms, SG&A expenses decreased by 7% compared to the prior year period.
SG&A expenses as a percentage of revenue improved to 21.1% compared to 24.6% we reported in the prior-year quarter, benefiting from cost management and reduced travel as we work through the uncertain COVID-19 environment.
R&D expenses for the quarter were $55 million, an increase of 14% over the prior-year quarter, or on a constant currency basis, an increase of 12%.
R&D expenses as a percentage of revenue was 7.3% compared to 7.1% in the prior year.
Total amortization of acquired intangibles was $20 million for the quarter, and stock-based compensation expense for the quarter was $16 million.
Non-GAAP operating profit for the quarter was $237 million, an increase of 24% over the prior-year quarter, reflecting strong top-line growth, expansion of gross margin, and well-managed operating expenses.
On a GAAP basis, our effective tax rate for the September quarter was 17.4%, while on a non-GAAP basis, our effective tax rate for the quarter was 18.5%.
Looking forward, we estimate our effective tax rate for the full fiscal year 2021 will be in the range of 17% to 19%.
Non-GAAP net income for the quarter was $185 million, an increase of 37% over the prior-year quarter.
Non-GAAP diluted earnings per share for the quarter were $1.27, an increase of 37% over the prior-year quarter.
Our GAAP diluted earnings per share for the quarter were $1.22.
Cash flow from operations for the quarter was $144 million, reflecting robust underlying earnings, partially offset by increases in working capital.
Capital expenditure for the quarter was $14 million.
Depreciation and amortization for the September quarter totaled $39 million.
During the quarter, we paid dividends of $57 million.
We recorded equity losses of $2.3 million in our income statement in the September quarter associated with the Verily joint venture.
We expect to record equity losses of approximately $3 million in Q2 and approximately $5 million per quarter in the second half of FY '21 associated with the joint venture operation.
We ended the first quarter with a cash balance of $421 million.
At September 30, we had $1.1 billion in gross debt and $635 million in net debt.
And at September 30, we had a further $1.2 billion available for drawdown under our existing revolver facility.
Today, our board of directors declared a quarterly dividend of $0.39 per share, reflecting the board's confidence in our strong liquidity position and operating performance.

Summary:
Non-GAAP diluted earnings per share for the quarter were $1.27, an increase of 37% over the prior-year quarter.
Our GAAP diluted earnings per share for the quarter were $1.22.