What happened

Garmin (GRMN 0.17%) shares beat the market month as the stock gained 11% compared to a 2% increase in the S&P 500 index, according to S&P Global Market Intelligence. The rally added to solid returns for the tech stock's shareholders, who are up 50% so far in 2019.

A hiker interacts with her smartwatch.

Image source: Getty Images.

So what

Garmin pleased investors with a third-quarter earnings announcement late in the month that showed healthy momentum across its GPS device business. Popular consumer smartwatch releases combined with hit aviation and marine products to send sales higher by 15%. Profitability improved, too, leading to a 27% surge in adjusted earnings per share.

Now what

Garmin is on track to notch its third straight year of accelerating sales growth and improving operating margins following management's 2019 outlook upgrade in late October. That prediction relies on a solid holiday season outing and includes the negative impact of its slumping auto GPS device division.

However, the tech stock's success at diversifying away from these volatile segments has lessened the risk involved with this business, and investors are responding to that improving earnings profile by sending shares significantly higher this year.