If you're in your 70s, you'll likely appreciate a rock-solid investment that can supply you with a steadily rising stream of income -- one that can help support you in retirement and that you can count on year after year.

Fortunately, there are a select few stocks that meet these criteria. Read on to learn about one of the best available in the market today.

A dollar sign with an arrow pointing to the right.

This dividend growth stock can add a cash-generating boost to your portfolio. Image source: Getty Images.

Microsoft (MSFT 0.43%) is a powerhouse business. The tech titan generated an incredible $33 billion in free cash flow during the past year, which helped its cash reserves grow to more than $135 billion at the end of the third quarter.

Microsoft's powerful cloud-computing operations are helping to drive these impressive results. The company successfully transitioned its Office franchise to a software as a service (SaaS) model; its cloud-based Office 365 service now has more than 135 commercial active users and 30.6 million consumer subscribers. Office 365 is enjoying torrid growth, with commercial revenue jumping 42% in the third quarter. Even better, Office 365 revenue is projected to become a $32 billion business for Microsoft by 2021, according to Evercore ISI.

In addition, Microsoft's enterprise-grade cloud computing platform Azure is taking share from industry leader Amazon Web Services. Azure's revenue soared 93% in the most recent quarter, while AWS revenue rose 49%. These results continue a trend in which Azure gained 4 percentage points of public cloud market share in the past year, according to a report by CNBC, while AWS' share fell by 6 percentage points. And with AWS still holding about 60% of the market compared to 20% for Azure, plenty of gains lay ahead for Microsoft if it can continue to close the gap with its larger rival. Better still, the market as a whole is growing rapidly, with IDC estimating that global spending on public cloud services will hit $266 billion by 2021, up from $128 billion in 2017. The cloud computing platform market, therefore, represents a massive long-term growth opportunity for Microsoft.

More profits for Microsoft equals more dividends for you

Microsoft excels at turning its growing revenue and earnings into cash for its investors. The company has boosted its dividend annually for 14 consecutive years, and its shares currently yield 1.8%. Importantly, dividend payments represented less than 40% of its free cash flow over the past year, so Microsoft has plenty of room to raise its payout. And with the company expected to grow its earnings per share by more than 10% annually over the next half-decade, investors can expect Microsoft to boost its dividend at an annual rate of 8% to 10%, or more.

All told, Microsoft is the type of stock that can fit well in a 70-year-old investor's diversified portfolio. Its strong cash generation and fortress-like balance sheet will help you sleep well at night. Its rapidly expanding cloud businesses should allow Microsoft to reward you with a steadily rising cash dividend stream. And with shares currently trading for around 21 times free cash flow -- a fair price to pay for such a high-quality business -- you may want to consider buying some Microsoft stock today.