What happened 

Auto parts retailer Advance Auto Parts (AAP 0.22%) shares declined nearly 18% in the week through Thursday afternoon. There are no prizes for guessing why: A disappointing set of third-quarter earnings released on Tuesday sent the stock crashing as investors ran for the exits. 

The company's comparable same-store sales declined by 0.7% in the quarter ending on Oct. 8. It's a figure notably below what its peers reported in their most comparable quarters. For example, O'Reilly Automotive reported a 7.6% increase in its comparable-store sales in its quarter ending Sept. 30, and AutoZone's domestic same-store sales increased 6.2% in its quarter ended Aug. 27.

So what

To be fair, part of the reason Advance Auto Parts' sales lagged behind its peers comes down to a conscious decision to increase sales of owned-brand products. They tend to carry lower prices (which reduces sales figures) but generate higher margins for the company. 

Still, on the earnings release, CEO Tom Greco said this strategy reduced comp sales by approximately 90 basis points.

If you add back those basis points, comparable same-store sales would have come to an increase of 0.2% -- still significantly below that reported by its peers. 

Now what

Unfortunately, it's far from clear that Advance Auto Parts is on track to generate operational metrics in line with its peers -- certainly not in terms of sales growth. As such, the case for the stock being a value play in the sector is unconvincing.