Stock declines continued last week as both the Dow Jones Industrial Average (^DJI 0.01%) and the S&P 500 (^GSPC 0.70%) shed over 14% in response to the economic disruption rippling through the economy from the COVID-19 outbreak.

Indexes are now down nearly 30% since the start of the year as investors struggle to estimate the impact of coronavirus and the related social distancing now being practiced around the world.

The path of that virus and the responses by world governments will move markets over the next few days, but there are also some highly anticipated earnings reports on deck from Nike (NKE 0.38%), Winnebago (WGO -0.03%), and lululemon athletica (LULU 1.09%). Below we'll take a look at the key trends that might send their stocks moving this week.

A young woman jogging over a bridge.

Image source: Getty Images.

Nike's China sales

Investors are eager to hear from Nike's management when it announces earnings results on Tuesday afternoon. The sports apparel titan had been posting impressive operating trends through the start of the 2019 holiday shopping season. But this week's report should contain more bad news than good.

The fiscal third quarter will reflect several weeks of the peak coronavirus outbreak in China, which accounted for $1 billion of incremental sales growth in Nike's last full fiscal year. As a result, the economic disruption and store closings in that market likely swamped whatever revenue gains the company might have seen in the core U.S. market, which grew 5% last quarter.

Investors will be even more interested in hearing how CEO Mark Parker and his team plan to weather the many demand challenges ahead, including suspended sporting events and shuttered stores across the U.S.

Nike's rebound pace in China might offer clues to the path that global sales could take once COVID-19 outbreak levels retreat in places like Europe and North America.

Winnebago's production plans

Winnebago will announce its earnings results on Wednesday morning, and investors will be watching for signs of collapsing demand in the recreational vehicle industry. The consumer discretionary company managed growth in both its towables and motorized RV segments last quarter, which made it stand apart from rivals like Thor Industries. Revenue jumped 19%, in fact, thanks in part to Winnebago's recent acquisition of the Newmar brand.

Cratering demand is likely, at least over the short term, as customer traffic falls to near zero at dealerships. That challenge will put the focus on Winnebago's cost infrastructure this week. CEO Michael Happe and his team will need dramatically slow production levels without compromising the company's manufacturing footprint or its ability to innovate, so look for management to dedicate most of its comments toward detailing its plan to balance those objectives through the downturn.

Lululemon's digital sales

Lululemon had solid momentum heading into the holiday quarter, and Thursday's earnings report should reflect that strength. Sales gains beat management's outlook for each of the prior three quarters of fiscal 2019, after all.

Looking back, it will be interesting to see whether the yoga apparel specialist protected its profitability in the context of rising tariff rates and increased competition. Executives predicted back in December that gross profit margin would rise in 2019 to mark a fifth consecutive year of gains.

The short-term outlook will be much cloudier thanks to store closures across the U.S. today. Look for Lululemon to try to quantify the impact of that move while also describing how e-commerce sales are holding up in the initial days of intense social distancing across the country.