Real Estate Trends Last  two years have been the strangest on record for the housing industry. An unprecedented housing boom increased throughout the 1990s and continued into the new millennium, thanks to relaxed credit standards, sinking interest rates, low unemployment and an insufficient housing supply. But signs now point to the impending end of the boom.   In more than 100 U.S. cities, home prices have climbed at least twice as fast as household incomes since 1998, according to The Wall S…