To minimize confusion with the implementation of the single security, the Federal Housing Finance Agency said it doesn’t plan to introduce new credit- scoring models until at least 2019. A number of groups have been pushing the government-sponsored enterprises to look beyond the FICO score, and Fannie and Freddie have been studying the issue. But FHFA Director Mel Watt said any major change would have to wait until the GSEs have completed the complex single-security project. “Based on the overwhelming feedback we have received from the industry, it is clear that it would be a serious mistake to change credit scoring models before mid-2019,” he told the annual convention of the National Association of Real Estate Brokers last week.