The most profitable retailers in sales per square foot are....

Sales per square foot are declining across the board. But some retailers continue to pull in hefty revenue.



The No. 1 retailer in terms of sales per square foot is Apple Inc., which does a staggering $5,546 per square foot, according to research provided by CoStar.



Apple is followed by Murphy USA, which leads the gasoline and convenience store retail industry with sales of $3,721 per square foot. Next up is Tiffany & Co., which leads the jewelry sector with sales of $2,951 per square foot. The top apparel retailer is Lululemon Athletica, with sales of $1,560 per square foot.



These top performers far outdistance the rest of the industry. According to CoStar, sales per square foot have declined to an average of around $325 in recent years, down from nearly $375 in the early 2000s.