Intuit (NASDAQ:INTU) has been on a tear recently -- not just its stock price, but its underlying business, too. The financial software company just wrapped up a fiscal year that marked a significant acceleration in its business. Intuit's year-over-year revenue growth rate accelerated from 10% in fiscal 2017 to 15% in fiscal 2018. Similarly, Intuit's fiscal 2018 growth in online ecosystem revenue was 40%, up from 30% growth last year. Finally, there's the fact that Intuit's revenue growth was at its highest in the final quarter of its fiscal year when revenue soared 17% year over year.

With such strong performance, not to mention Intuit's 59% rise in its stock price over the last 12 months, expectations are high for the company's fiscal 2019. While some deceleration in Intuit's business growth in fiscal 2019 would be natural, there's good reason to expect more solid performance from Intuit.

A small-business owner using QuickBooks Online on a tablet

Intuit's QuickBooks Self-Employed. Image source: Intuit.

Two quotes from Intuit's fourth-quarter earnings call capture why more strong momentum is likely.

Intuit's online ecosystem revenue has surged

Intuit's online ecosystem revenue, which measures sales from Intuit's online products and services within its small-business and self-employed group, importantly saw accelerated revenue growth in the company's final quarter of the year. Online ecosystem revenue climbed 43% year over year, up from 41% growth in Q3.

Online ecosystem revenue has become integral to the company's business, according to Intuit's soon-to-step-down CEO Brad Smith.

"Online ecosystem revenue growth has emerged as the best gauge of health and success of this business, and it now represents more than $1 billion [annually]," Smith explained. And Intuit expects more strong growth ahead for this revenue category. The company continues to expect online ecosystem revenue "to exceed 30% growth year-over-year," said the CEO.

More material to Intuit's business than ever before, online ecosystem revenue will help drive strong growth for Intuit in fiscal 2019.

Payroll and Payments: Key to online services growth

One often overlooked key metric Intuit reports is its year-over-year growth in online services revenue. Online services revenue measures growth of the services within Intuit's online ecosystem revenue category. Growth in Intuit's online services revenue accelerated sharply in Q4; online services revenue increased 27% year over year in Q3 and then rose 34% year over year in Q4.

Smith explained the interesting way the company has found to drive accelerating growth for its online services. Beyond the continued rapid growth it's seeing from selling payroll and payments services to QuickBooks Online customers, Intuit has also benefited from reversing this model -- selling QuickBooks Online to payroll and payments customers:

This past quarter, Online Payroll attached to QuickBooks Online grew faster than 30%. And Payments grew faster than 40%. Now you introduce these new opportunities to have those services be the first experience for a customer, whether it's GoPayment for payments or it's Payroll, and then unlock the QBO, and we think that's really going to give us an opportunity to accelerate our services business. So we are in a razor-and-blade business. We feel like there is a lot of game left in the razors, but we have gotten smarter, and now we're entering that chapter where the blades are going to become more important. And we do expect that you're going to see online services continue to grow and accelerate.

Management said it expects its fiscal 2019 revenue to rise 8% to 10% year over year. Of course, the company's guidance has consistently proven to be conservative, making more double-digit revenue growth in fiscal 2019 likely.

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