The Association of Research Libraries has released a PDF version of ARL Preservation Statistics 2005–06, which is freely available.
Here's an excerpt from the "Introduction":
Among the significant developments that took place in research libraries in the 1980s was the emergence of preservation programs as distinct administrative units, separately staffed, funded, and administered. There were 66 such programs reported in 1988, as many as 80 reported in recent years, and 77 in 2005-06.
These rapidly shifting trends have made themselves evident in many categories. Preservation expenditures for ARL’s 111 reporting member libraries were $107,937,836 in 2005-06, which reflects an inflation-adjusted increase of 27% since the survey’s revision in 1996-97.3 Total preservation staff increased to just under 1,800 FTEs in 2005-06, 5.4% more than in 2004-05. Level 1 conservation treatment decreased from 2004-05 levels, while the number of items treated at Levels 2 and 3 increased; total conservation has increased by more than 50,000 volumes in the past year, bringing it higher than it has been in the last four years. . . .
Digitizing bound volumes is gradually emerging as a viable preservation option. In 2005-06, 54 ARL libraries reported more than zero bound volumes digitized. The amount of items digitized varies widely, from one volume at the University of Delaware to 25,121 volumes digitized by the University of Florida.