S&P 500 top movers: Best Buy Co Inc (BBY:NYSE) drops more than 10% on dismal sales

• S&P 500 Index is down more than 2% on the day.
• Best Buy Co Inc (BBY:NYSE) shares suffer heavy losses after Q4 sales miss.
• Quanta Services Inc (PWR:NYSE) on strong earnings figures.

The S&P 500 Index (SPX) started the day with modest losses but came under strong bearish pressure with safe-haven flows continuing to dominate the financial markets. As of writing, the SPX was losing 2.2% on the day at 3,838.

S&P 500 top movers

Earlier in the day, Best Buy Co Inc (BBY:NYSE) announced that it forecasts full-year comparable sales between a fall of 2% and a rise of about 1%, compared to market expectation for an increase of 1.6%. On a positive note, the consumer electronic retailer registered a fourth-quarter profit of $3.48 per share versus analysts' estimate of $3.45. Nevertheless, BBY came under heavy selling pressure and was last seen losing 10.3% on the day at $63.25.

On the other hand, Quanta Services Inc (PWR:NYSE) stock is the biggest daily percentage gainer on Thursday after the company reported a 42% increase in quarterly net income. The infrastructure contracting service provider also announced that it targets a 2021 revenue in the range of $11.95-$12.35 billion, compared to analysts' estimate of $11.90 billion. Boosted by the upbeat report, PWR jumped to a new all-time high and was last seen gaining nearly 5% at $85.