Hong Kong (CNN Business) China and the United States are locked in a trade war, but you wouldn't know it from looking at Chinese exports.

They leaped almost 16% in October compared with the same month a year earlier. That was significantly higher than analysts had forecast and even stronger than last month's growth

The performance is surprising because October was the first full month during which new US tariffs on $200 billion of Chinese goods were in effect. Economists and Chinese government officials said recently that they expected export growth to slow in the final months of the year.

One reason for the surge is companies are eager to avoid even higher duties in a few months' time: The US tariffs on $200 billion of Chinese goods that kicked in on September 24 are set to rise from 10% to 25% at the end of the year.

This "encourages exporters to rush through orders to the United States," Louis Kuijs, head of Asia economics at research firm Oxford Economics, wrote in a client note Thursday. But he added that it's "obviously not the whole story."

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