"A high percentage are involuntary retirees," said Ronald F. Pollack, president of Families USA, a health care advocacy group representing people of all ages.

"After so many years of this, people have forgotten that we should be asking for the whole fix, not just little pieces," said Julie Stewart, president of Families Against Mandatory Minimums.

"It's a very good thing the president did, because it's a marker," said Judith L. Lichtman, president of the National Partnership for Women and Families, a liberal advocacy group.

But Carie Lemack, president of Families of Sept. 11 who lost her mother in the terrorist attacks, said the measure was essential.

Geoffrey Canada, the president of the Rheedlen Centers for Children and Families in Harlem, said he had not expected to see such a drop for three or four more years.

However, Ms. Lemack, the president of Families of September 11, an advocacy group that represents some relatives of victims of the attack, said that she had not seen the tape.

"We've got all kinds of horror stories," said Carie Lemack, president of Families of Sept. 11, a victim advocacy group.

Geoffrey Canada is president of Rheedlen Centers for Children and Families, a nonprofit youth group.

The July commutations "made us realize Clinton was likely to do more," said Julie Stewart, president of Families Against Mandatory Minimums.

He is president of the Rheedlen Centers for Children and Families, a group based in Harlem that aids poor children.