Apple just added a Ford. Stock up $48 billion in a single day

David Paul Morris | Bloomberg | Getty Images

Tim Cook, chief executive officer of Apple speaking with dancer Maddie Ziegler during an Apple event in San Francisco.

Apple, the world’s most valuable company, added more worth in one day than the market cap of nearly 400 individual companies in the S&P 500.

The smartphone maker’s shares surged 6 percent to a new all-time high at Wednesday’s open, a day after it reported better than expected earnings. The gain represented $48.1 billion of additional value for Apple shareholders to an approximately $830 billion total market value.

The single day increase is more than the market value of Ford Motor and 392 companies in the S&P 500, according to FactSet.

Apple’s cash pile rose to a record $261.5 billion, which is enough to buy Wal-Mart outright at its $243 billion market cap.

The technology company has been one of the best-performing large-cap stocks in the market. Its shares rallied 29.6 percent year to date through Tuesday versus the S&P 500’s 10.6 percent return.