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

• Apple adds more value in a single day than the worth of nearly 400 individual S&P 500 companies.
• Wednesday's gain represented $48.1 billion of additional value for Apple shareholders to an approximately $830 billion total market value.
• Ford's current market capitalization is about $43.6 billion.

Apple, the world's most valuable company, added more worth in one day than the market cap of nearly 400 individual companies in the .

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 stock closed up 5 percent Wednesday.

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.

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