Public pension plans are adding risk to raise returns

States and companies have started investing very differently when it comes to the billions of dollars they are safeguarding for workers' retirement. Companies are quietly and gradually moving their pension funds out of stocks. They want to reduce their investment risk and are buying more long-term bonds. But states and other bodies of government are seeking higher returns for their pension funds, to make up for ground lost in the last couple of years and to pay all the benefits promised to present and future retirees. Higher returns come with more risk.