The United States has defied regional trends in 2021 to increase its influence in the Indo-Pacific while China's has waned, according to an assessment released by an Australian think tank on Sunday.

The Asia Power Index, released yearly by the independent Lowy Institute in Sydney, ranks 26 countries and territories in the Indo-Pacific according to the power they have in the region. Power is measured in eight categories, including military capability, economic resources and diplomatic influence.

Almost all countries lost power amid the coronavirus pandemic in terms of their capacity to respond to and shape their external environment, but the United States was a rare exception, according to the think tank.

The United States saw the first annual gain in comprehensive power since the think tank began publishing the annual assessment in 2018, posting the greatest upswing of power in the region after experiencing the largest drop in 2020.

In terms of scores, the report found the United States maintaining its position as the most powerful country in the region with 82.2 points, improving its lead over China by 2.1 points since last year.

Meanwhile, China's power has fallen for the first time since the ranking began to 74.6 points, "with no clear path to undisputed primacy in the Indo-Pacific," according to the report.

The findings showed that China retains significantly greater influence than the United States in economic relationships. However, for the first time the United States surpassed China in the measure of future resources as Beijing faces the growing burden of an aging population, climate change vulnerabilities and an inward-focused political system.

While China's economy will still likely overtake that of the United States, "Beijing is now less likely to pull ahead of its peer competitor in comprehensive power by the end of the decade," according to the report. "This suggests that there is nothing inevitable about China's rise in the world. It appears very unlikely China will ever be as dominant as the United States once was."

The United States also narrowly overtook China and Japan in the region for diplomatic influence in 2021, thanks in large part to vaccine diplomacy, dubbed "the new currency of geopolitics" by the index.

Japan's third-place ranking remained unchanged, but for the first time the country's score fell below the major power threshold of 40 points to 38.7, and it is now considered a high performing middle power. The country, however, continued to be described as the "quintessential smart power" wielding broad influence in the region despite its limited resources.

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