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The Dow Jones Industrial Average, a basket of 30 major US stocks, glided past 22,000 points for the first time ever on Wednesday, lifted by a rise in Apple shares.

The milestone marked the latest in a streak of share price gains since January, but some are worried about the future strength of the rally.

The wider S&P 500 index rose just 0.05% to 2,477.57, while the tech-focused Nasdaq held steady at 6,362.65.

The Dow ended at 22,016.24, up 0.24%.

The Dow has risen almost 11% since the start of the year. The S&P is up about 10%, while the Nasdaq has climbed about 17%.

Analysts first said the stock rally was due to optimism about President Donald Trump's business-friendly policies such as corporate tax reform. Now they say strong corporate earnings are boosting share prices.

The markets' rise on Wednesday was attributed to reaction to earnings from technology giant Apple.

Shares of the California company closed 4.7% higher after the firm reported strong sales of iPhones, iPads and other services.

But the gains weren't felt everywhere.

Media giant Walt Disney shares fell 1.75%, while telecommunications company Verizon fell 1.4%