TANABE -- Outside of densely populated cities characterized by skyscrapers and tiny apartments lies another Japan. In much of this world, akiya, abandoned homes, and akibiru, abandoned buildings, form the backdrop to everyday life -- not a picture one immediately associates with the hustle and bustle of the world's third largest economy. But if current trends continue, more than 30% of Japan's housing stock -- 22 million units -- will be derelict by 2038, Nomura Research Institute predicts.