China has surpassed Japan as the world’s second-largest economy behind the United States, according to government figures. Tokyo said early on Monday morning that Japan’s economy was valued at $1.28 trillion in the second quarter. China’s economy, meanwhile, came in at just under $1.33 trillion. “This has enormous significance,” said Nicholas Lardy, an economist at the Peterson Institute for International Economics. “It reconfirms what’s been happening for the better part of a decade: China has been eclipsing Japan economically.” China’s economy, for the rest of the year, is expected to grow at about a rate of 10 percent, adding to a three-year run of double-digit growth.