With Starbucks (NASDAQ:SBUX) reporting financial results for its 2021 fiscal fourth quarter on Oct. 28, investors have a lot to pay attention to. The ubiquitous coffeehouse chain continues to benefit from strong momentum thanks to the loosening of pandemic restrictions and the increase in consumer mobility.

If you own the stock, there are some key trends to zero in on. Three in particular could have a huge impact on Starbucks and its shareholders.

Starbucks employee with mask on.

Image source: Starbucks.

1. Rewards members 

You can't talk about Starbucks without discussing its top-notch loyalty program. At the end of the previous quarter, there were 24.2 million active rewards members in the U.S. and 17 million in China. These loyal customers provide Starbucks with an extremely valuable channel to drive higher levels of engagement and encourage repeat business. 

In the U.S., these customers represented more than half of all sales at company-operated stores. So, it's easy to see how important they are to Starbucks' success. Plus, the mobile app gives consumers more ways to order up their favorite beverages. "With drive-thru representing 47% of transactions and mobile ordering for in-store pickup, delivery, or curbside at 26% of transactions, we are leveraging all channels to better serve our customers," CEO Kevin Johnson pointed out on the Q3 earnings call.  

This robust digital infrastructure, which helps the company engage with consumers, is part of what makes Starbucks one of the best restaurant stocks to own. Look for continued membership growth in the upcoming earnings release. 

2. Growth in China

In the most recent quarter, revenue from Starbucks' China segment totaled $905 million, or 12% of the overall business. As is the case with many American consumer brands, this region has been a fast-growing segment for Starbucks. The company now has 5,135 stores in China, with plans to end fiscal 2021 having opened 600 additional net new locations there. That's more than half of the 1,100 total stores Starbucks will open globally in fiscal 2021. 

"There should be no misunderstanding of how big and robust our business in China is and will be. These are still early days, and our strategies are clearly working," Johnson said. Like here in the U.S., it's all about creating an exceptional consumer experience in China, where Starbucks has been operating now for over 20 years. 

Same-store sales in China are expected to increase 18% to 20% in fiscal 2021 compared to the prior year. This is down from previous guidance of 27% to 32% growth, so investors will want to pay attention to any commentary regarding demand trends in the most populated country on Earth. 

Management has huge ambitions to reach a worldwide footprint of 55,000 stores by 2030. China will undoubtedly play a big part in that push. 

3. The pandemic's impact

As a result of the different levels of progress being made against the coronavirus in various markets, Starbucks' reopening cadence has been uneven. In the U.S., things look to be trending positively over the past few months as many restrictions loosened and consumers felt comfortable venturing back out again. Consumer mobility is crucial for Starbucks, as people who are on the go find more occasions throughout the day to stop by a location. 

"Not only have we posted incredible results as we emerge from the pandemic, our internal research also confirms Starbucks has gained meaningful market share in the U.S.," Johnson said. Even if stores remain closed for in-store dining, the digital prowess mentioned earlier reduces friction for customers and lets Starbucks shine while independent coffee shops struggle to keep up. 

In America, transaction counts in the latest quarter were at 90% of pre-pandemic levels. If Starbucks continues to see this figure creep higher that's clearly an extremely positive sign, especially for a company whose success is dependent upon frequent customer visits and purchases. Any change in consumer behavior, particularly as it relates to the coronavirus heading into the fall and winter months, is important for shareholders to focus on. 

Starbucks reports fresh financial results on Oct. 28. Watch for the growth in loyalty members, the ongoing expansion in China, and any color on the pandemic's effects. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.