This review of the Changes album comes from the June 13, 1970 issue of Billboard.
UPDATED 5/27: Thanks to Gilbert Matthews for some further information about Changes on the Billboard charts that appears in the comments section of this post. Though Changes didn't chart when it was originally issued (it finally made an appearance on Billboard upon its 1986 re-release), Gilbert mentioned that he saw the album listed in a chart called "Action Records" in the July 11, 1970 issue of Billboard. I was able to track down an image of it below:
What are Action Records? In the book The Billboard Book of Top 40 Albums, author Joel Whitburn describes Action Records as "stereo/mono albums charted nine weeks or less." So, perhaps Changes ended up in this category at the time since it was a new release (having been issued in June 1970). Based on my research, it doesn't have anything to do with sales. Nonetheless, very interesting! Thanks, Gilbert, for this tidbit.
UPDATED 4/16/14: "Oh My My," the first and only single from the Changes album, made an indent on the charts, even if it was only regional in nature.
Interview with Wayne Avers