Report: Japan, Russia to Lose Population WASHINGTON - Japan, Germany and many other large industrialized countries face long-term population slowdowns or declines as more young adults have fewer children or delay child-rearing, demographers say.    While the world's population is expected to increase by almost 50 percent by 2050, Japan could lose 20 percent of its population over the next half-century, according to data released Tuesday by the private Population Reference Bureau...