iRobot (IRBT 1.20%) stock price surged in 2020 after an initial sales slump from the pandemic gave way to surging demand for its premium robotic vacuum cleaners. Consumers prioritized spending on home maintenance last year, and federal stimulus checks supported that bigger budget.

CEO Colin Angle and his team back in February projected that iRobot's momentum will carry on into 2021 even as the pandemic threat fades and spending patterns fall back to normal levels.

That bright outlook will be put to the test when iRobot reports fiscal first-quarter results in just a few days. Let's look at the standout numbers to follow in that announcement, set for Tuesday, April 27.

A robotic vacuum at work cleaning a floor.

Image source: Getty Images.

1. Pricing trends

iRobot capitalized on intense growth in its industry niche, with sales jumping 28% year over year in the fiscal fourth quarter. That increase came mostly from higher volumes, which rose to 2.2 million unit sales from 1.9 million a year earlier. But the company also boosted average selling prices up to $327 from $317.

We'll get a good indication this week about whether that price boost was driven more by iRobot's product innovations or by the temporary lift provided by federal stimulus checks. Another healthy mix of price and volume gains would add weight to management's claim that iRobot is building a deeper relationship with its customers and delivering tons of value to them through enhancements to its hardware and software services. Overall, most investors are expecting sales to jump 39% to $268 million this quarter.

2. Profitability

iRobot is in the process of shifting production from China to Malaysia. Its sales have also been tilted in recent quarters toward new releases that aren't as efficient to produce as prior vacuums have been.

These trends combined to push gross profit margin down for a second straight year last year, but a key pillar of the growth thesis relies on that figure starting to climb back toward 50% of sales in late 2021 and into 2022.

IRBT Gross Profit Margin Chart

IRBT Gross Profit Margin data by YCharts.

Investors won't see much progress on this score at the start of fiscal 2021. In fact, operating income is projected to drop this year as iRobot works through its manufacturing shift. But look for executives to highlight trends that are supporting the rebound, including higher direct-to-consumer sales and a rising interest in subscription services.

3. The new outlook

A lot has changed since iRobot issued its first official 2021 outlook back in February. Vaccine availability has reopened many local markets, while broader economic growth looks strong.

We'll find out if these dynamics have convinced Angle and his team to change their tune on the current fiscal year. Heading into the report, they were projecting sales would rise to between $1.64 billion and $1.68 billion this year from $1.4 billion in 2020. Operating margin was slated to fall to between $110 million and $120 million compared to $146 million last year.

Each of these forecasts could change in response to the latest industry dynamics. Strong demand might power an upgrade on Tuesday. Rising competition, on the other hand, or shipping and manufacturing struggles could lower the outlook. In any case, investors should brace for a volatile trading week ahead for iRobot stock.