Tractor Supply Company (NASDAQ:TSCO) shares are trading lower in the premarket session after the company reported third-quarter results. Quarterly earnings per share of $2.24, in line with the analyst consensus. Third-quarter net sales of $3.47 billion (+1.6%) missedthe street view of $3.485 billion. The increase in net sales was driven by new store openings. Comparable store sales declined 0.2% yearly, driven by a comparable average transaction count increase of 0.3%, offset by a comparable average ticket decrease of 0.5%. Gross profit increased 3.2% to $1.29 billion, and gross margin increas…