Tractor Supply on Wednesday evening told investors it had a strong end to 2011, with same-store sales growing 7.6 percent from a year before and total revenues jumping by a fifth to $1.24 billion, about 7 percent higher than the company had forecast in October.

Because of that, Chairman and CEO Jim Wright said his team now expects to post a 2011 profit of $2.97 to $2.99 per diluted share, up from its previous guidance of $2.85 to $2.89 per share. (The latter number was itself an increase from Tractor Supply's summer outlook.) Of the increase, between 3 and 4 cents is from the 53rd week Tractor Supply included in its fiscal 2011. Those extra selling days also accounted for 1.1 percentage points of the 7.6 percent same-store sales increase.

"These results are reflective of the structural improvements we have made to our business in recent years," Wright said. "Sales growth in the fourth quarter of 2011 was driven by continued strong transaction count and a year-over-year increase in average ticket, with added tailwinds from both the 53rd week and inflation."

Shares of Tractor Supply (Ticker: TSCO) rose almost 5 percent in after-hours trading Wednesday to $76.53. The median price target among analysts, whose consensus estimate already was above Tractor Supply's earlier guidance, stood at $79.50 Wednesday.