What happened

AutoZone (NYSE:AZO) shareholders outperformed a booming market last year as the stock jumped 43% compared to a 29% spike in the S&P 500, according to data provided by S&P Global Market Intelligence.

Shares tracked ahead of the market for most of the year, with investors enjoying some of their strongest returns late in 2019.

A man shops for engine oil.

Image source: Getty Images.

So what

The auto parts retailer benefited from generally positive selling conditions as the average age of cars on the road continued to rise, pushing demand for maintenance higher. But AutoZone also notched a few important strategic wins last year, including its move deeper into the commercial space and a restructuring of its supply chain. Those successes, plus a booming e-commerce selling channel, helped keep comparable-store sales growth steady at about 3% in each of the last three quarters. 

Now what

Investors like AutoZone stock for its rare ability to grow during expansions and recessions, and that attraction is likely to keep interest in the stock high into 2020. A further rally in shares will depend on the retailer continuing to show market-beating sales growth, though, even as it expands its footprint in the U.S. and across international geographies such as Brazil and Mexico.