"Clearly a living fabric has come undone, and we, like weavers, are called to repair it," said Pope Francis in the letter. He also noted perceived divisions among the American bishops, and said that a unified body would help to re-establish credibility among Catholics.
Catholic confidence in clergy has wavered over the last decade and a half.
In 2008, 63 percent of American Catholics said that they had a "high" or "very high" view of the ethical standards of the clergy. This number dropped nine points, to 54 percent, by 2011.
Following the election of Pope Francis in 2014, the number rose to 57 - the last year in which topped 50 percent.
Other Gallup polls have offered different indicators about the state of the Church in the United States. The number of Americans who identify as Catholic has remained roughly stable at around 25 percent throughout the last seven decades. Conversely, the number of self-identified Protestants has dropped, and the number of people with no religious affiliation, self-identified "nones," has risen.
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Additionally, over half of Catholics surveyed in 2018 say that religion is a "very important" part of their lives. This figure, too, has remained relatively stable since 2001.
One area that has not remained stable is Mass attendance. From 2014-2017, not a single age group of Catholics reported a majority attending Mass each week. In 2018, only about 36 percent of Catholics said they had been to Mass within the last week. That number is a drop from 45 percent in 2008, and 75 percent in 1955.