Analysts downgraded shares of auto parts retail giant AutoZone on Tuesday, May 23, after the company reported a second straight quarter of weaker earnings and sales for its fiscal third quarter.

Raymond James Financial Inc. lowered its rating on AutoZone’s stock from “strong buy” – which it attached to AutoZone back in September 2007 – to “market perform.”

“While valuation metrics for AZO remain attractive, most of the key metrics we use to evaluate retailers have taken a turn for the worse over the past two quarters,” Raymond James wrote in comments distributed after AutoZone’s quarterly presentation to analysts. “We believe we have been sufficiently patient with AutoZone, but the poor F3Q17 results can no longer support a Strong Buy rating.”

The quarter’s results followed the trend from last quarter, when weaker performance ended AutoZone’s 41 straight quarters of double-digit earnings per share growth.

A Tuesday, May 23, article about AutoZone in Barron’s displayed the headline “Not So Immune After All,” referring to a longstanding theme at the company that its business model is somewhat insulated from broader retail industry challenges.

Shares of AZO hit a new 52-week low intraday Tuesday below $600 a share. The stock’s 52-week high is $819.54.

AutoZone reported net sales of $2.6 billion for the quarter ended May 6, up 1 percent from the year-ago quarter. Domestic same store sales – which focus on sales at stores open for at least a year, a key retail industry metric – were down 0.8 percent in the quarter.

The company posted a 1.3 increase in net income for the quarter over the same period in 2016, to $331.7 million.

AutoZone chairman, president and CEO Bill Rhodes acknowledged the quarter’s weakness in a presentation to analysts Tuesday, telling them that the company seems to be caught up in challenges that are “broad-based across our industry and other sectors of the economy.”

As the company reached the end of the quarter, he continued, it felt sales had begun to stabilize and get back to normal. Nevertheless, Rhodes said the company saw “sluggish customer demand” across virtually every category.

And there were other reasons he pointed to for the slump.

“We’ve made decisions to accelerate some investments in our business,” Rhodes told analysts, noting that the company is investing at an increased rate in its inventory, in capital expenses and has increased its operating expenses as part of its more frequent delivery and mega-hub efforts.

He said pressure on wages has also accelerated over the last two years.

While the company will look to see if any of its recent decisions need to be adjusted, Rhodes stressed that “our management team has been in this business for a long time …. (and) we’ll continue to manage this business for the long term.”

AutoZone bought back 396,000 shares of its stock for $284 million during the quarter. The company had a little more than $1 billion left under its current share repurchase authorization.

AutoZone also opened 35 new stores in the U.S. during the quarter. As of May 6, the company had a total store count of 5,915.