If Japan and other aging countries created a sovereign wealth fund funded by taxes during "boom" times, like Norway has done, then it wouldn't be as dependent o

If Japan and other aging countries created a sovereign wealth fund funded by taxes during "boom" times, like Norway has done, then it wouldn't be as dependent on a pay-as-you-go system. This fund would be held in other currencies and could be drawn down as necessary to keep the local currency stable in the absence of exports. True, much of the domestic economy would be providing care to older people (and few tangible exports) but distributions from the sovereign wealth fund would ensure the Japanese still have a high standard of living. Pay-as-you-go social security systems are the real problem, not low birth rates.