This simple report takes all clients who have stayed in the selected shelter(s) in the date range, and counts the total number of nights they stayed in shelter during that date range. The graph then sorts the clients by the total number of nights in shelter during the range. Note that this report works best if you select a long date range, like 1 year.
This report is a free tool that's a companion to my data wizardry presentation, You're Probably Lying About Homelessness, which you can watch on the webinars archive page.