Japan also has a large current account surplus, and in 2009 and 2010 the country allowed the Yen to appreciate. However, in September 2010 Japan twice intervened to effect a devaluation. Japan has a number of challenges that limit its ability to allow ongoing currency appreciation, including an aging population, high government debt (though not net debt as it has high private savings) and vulnerability to deflation. The September devaluation did not draw widespread international condemnation. Within a couple of weeks upwards pressure on the Yen from the markets had almost entirely undone the effect of the intervention. However shortly after the March 2011 earthquake, other G7 nations joined Japan in a rare act of solidarity, selling billions of Yen to help Japan devalue its currency against pressure from speculators who were betting on a further appreciation, as insurance firms recalled funds from abroad.