Key Freddie Mac executive steps down: filing Mon Apr 30, 2012 10:15pm EDT (Reuters) - A top executive at Freddie Mac (FMCC.OB) is leaving the mortgage buyer a year after he was appointed to head its single-family business. The regulator for Freddie Mac and Fannie Mae (FNMA.OB) responded to political pressure in March by slashing salaries for the chief executives of the two firms and ruling out bonuses for many top executives. The companies, which guarantee half of all U.S. mortgages, have soaked up about $170 billion in taxpayer aid since they were taken over in the wake of the 2008 financial crisis. Freddie Mac said in a filing with the U.S. Securities and Exchange Commission that Anthony Renzi, a member of the company's management committee reporting directly to the Chief Executive, would leave the company on May 11. Charles Halderman Jr, Freddie Mac's CEO, has also expressed his desire to step down from the government-controlled mortgage firm. Revelations that Freddie Mac and Fannie Mae, the two largest sources of U.S. mortgage finance, were paying out $12.79 million in bonuses for 10 executives caused an uproar on Capitol Hill last fall among Democrats and Republicans. Before joining Freddie Mac, valued at $187.1 million, Renzi worked at GMAC Mortgage for 25 years. Reporting by Sunayan Bhattacharjee in Bangalore