Hillary Clinton's image has plummeted to its lowest level in the two decades Gallup has tracked her standing with the public.

Her favorability rating has dropped from 59 percent in 2015 to 38 percent this month, a record low. Clinton's unfavorability score has skyrocketed from 36 percent early last year to 57 percent now, the July 16-23 survey found.

Even at the height of investigations into the former secretary of state's actions during the 2012 attack on the U.S. Consulate in Benghazi, Libya, Clinton had a 55 percent approval rate.

Clinton had been on a downward spiral since last year's email scandal surfaced. Her tenure with majority approval slipped early this year. By mid-June, only 41 percent of voters had a positive view of her.

Republican nominee Donald Trump still fares worse than his rival. Over the past seven days, Trump had a 36 percent favorability score and 59 percent unfavorability rating.

A random sample of 3,545 national adults were interviewed in the telephone survey. The poll had a 3 percent margin of error.