The S&P 500 has gained 2.44% since the close last Thursday, but the average stock in the index has gained 2.26%. This means that the largest stocks in the index have outperformed the smaller ones since it's a cap-weighted index. With a gain of more than 7%, Apple (NASDAQ:AAPL) has been a key driver of performance over the last 2+ trading days.
You can see Apple's impact when looking at the performance of the ten S&P 500 sectors as well. Below is a chart showing the performance of the ten S&P 500 sectors since last Thursday's close along with the average performance of the stocks that make up each sector over the same time period. While the Technology sector (the weighted index) is up 2.6%, the average stock in the sector is up just half that at 1.3%. Aside from Apple, the Technology sector has actually been underperforming by a wide margin during this bounce.
While Technology has lagged, Consumer Discretionary, Materials, Energy and Financials have been the leaders during this rally. (Along with Apple.)