New York State regulators are calling for a nationwide moratorium on transactions that life insurers are using to alter their books by billions of dollars, saying that the deals put policyholders at risk and could lead to another taxpayer bailout, the New York Times DealBook blog reported today. Insurers’ use of the secretive transactions has become widespread, nearly doubling over the last five years. The deals now affect life insurance policies worth trillions of dollars, according to an analysis done by SNL Financial, a research and data firm. These complex private deals allow the companies to describe themselves as richer and stronger than they otherwise could in their communications with regulators, stockholders, the ratings agencies and customers, who often rely on ratings to buy insurance. Benjamin M. Lawsky, New York’s superintendent of financial services, said that life insurers based in New York had alone burnished their books by $48 billion, using what he called “shadow insurance,” according to an investigation conducted by his department.