What happened

Five Below (FIVE 1.55%) stock gained 12% last month, according to data provided by S&P Global Market Intelligence, compared to a 2.8% increase for the broader stock market.

FIVE Chart

FIVE data by YCharts.

The rally added to market-thumping gains for the youth-focused retailer's shareholders, who are up over 60% in 2017 while the S&P 500 has gained 18%.

So what

Like many of its retailing peers, Five Below announced better-than-expected third-quarter sales results last month. But its growth metrics are strong enough right now that it is standing out from the crowd.

Comparable-store sales were up 8.5%, the company revealed on Nov. 30, which blew past management's forecast of between 3% and 5% gains. Five Below expanded profitability during the quarter, too, as young shoppers responded enthusiastically to its merchandising and marketing efforts.

Now what

CEO Joel Anderson and his team lifted their full-year forecast on both the top and bottom lines and they now see comps rising by between 5.7% and 6.5%, compared to the prior target range of 3.5% to 4.5%. Five Below's overall revenue base will grow at a much faster rate, since the company aims to open as many as 100 new locations this year, including in many new markets.

Two young women smile while shopping.

Image source: Getty Images.

The retailer has 600 stores across 32 states today, but with comps expanding at a market-beating rate right now, management's hope of eventually reaching 2,000 locations is looking more achievable with each passing quarter.