In many ways, 2020 was a challenging year for McDonald's (MCD 0.07%) as the coronavirus pandemic wreaked havoc on its worldwide business. Now, as it prepares to report first-quarter 2021 earnings on Thursday, April 29, international economies are on divergent paths.

In the U.S., many states are feeling comfortable easing restrictions on restaurants as a big part of the population is getting protection against infection through vaccination. Other parts of the world are not as fortunate, and lockdowns and restrictions are the norms rather than the exceptions. Against that backdrop, here are three things you're going to want to know when McDonald's reports Q1 earnings. 

French fries on a cutting board.

Image source: Getty Images.

McDonald's rebound is one-sided

First, make note of the overall rate of comparable-store sales growth, which excludes the effects of new restaurant openings and closings. There are two stories playing out with McDonald's comp sales growth: Increasing comps in the U.S. and declining comps internationally. In the U.S., comparable-store sales increased by 5%. That may encourage shareholders who might extrapolate positive growth in other parts of the world when vaccination rates accelerate and restrictions on restaurants are reduced.

Second, those interested in McDonald's stock will want to look at operating income. The figure declined by 7% in the most recent quarter as the company continues to account for the adverse effects of COVID-19 on its business. In addition to putting pressure on sales, the pandemic brings about higher costs. For instance, digital orders for delivery have surged. These sales are less profitable for McDonald's because it has to pay higher costs for fulfillment. Among the folks who feel more comfortable leaving their homes, some will return to dining at the restaurant, which will be a boom for profits in the next few quarters. 

Third, if you follow the stock, you will want to get some insight from management on how the business is evolving as states ease restrictions on dining inside at restaurants. It will also be helpful to compare the differences between U.S. locations and those from the international segment, as the latter is still facing lockdowns and restrictions in several countries. Investors will want to know whether the positive effects of easing restrictions in the U.S. outweigh the negative effects of surging coronavirus cases in other parts of the world. 

What this could mean for investors 

Analysts on Wall Street expect McDonald's to report revenue of $5.04 billion and earnings per share of $1.81, which would be increases of 6.8% and 23.1%, respectively, from last year. Its shares are up over 9% year to date, which could be an indication investors anticipate a strong recovery when more people get vaccinated worldwide.

Despite all its challenges, McDonald's still generated $4.6 billion in free cash flow for 2020, down from $5.7 billion in 2019. That's a testament to its ability to adapt to circumstances. Investors looking for a stock with a long history of excellent performance can feel good about adding McDonald's to their watch list.