It’s not every day that a stock comes public at $20 a share, falls 7 percent on its first day of trading and then continues to drift downward. Then again, if that stock is a mortgage investing real estate investment trust like Cherry Hill Mortgage Investment Corp., it’s no big surprise. Thanks to rising interest rates – which actually have been in decline during the government shutdown and uncertainty over the U.S. debt ceiling – mortgage REITs have been battered in the market. Cherry Hill, a spin-off of Freedom Mortgage of Mt. Laurel, NJ, went...