A Publication of the Public Library Association Public Libraries Online

80/20 Collection Development

by on November 15, 2012

I’m a big fan of the 80/20 rule, 80 percent of the gain comes from 20 percent of the effort, and 20 percent of the gain takes 80 percent of the effort. What if we applied the science and wisdom of the 80/20 rule to our collections and weeding, could libraries radically increase our circulation and relevance to the community? I believe that we can, let me explain.

How does the 80/20 rule apply to library collections? Easy, 80% of the library’s circulation comes from 20% of the items. If librarians look at their circulation stats, this becomes painfully obvious. Why not mine those statistics to see where to increase and decrease spending, what collections can be phased out, where do we need to bulk up, what are we doing well and what are we doing poorly?

In my library, books don’t even crack the top 400 items checked out, it’s all DVDs and video games, and yet these items only account for a small percentage of the materials budget. Part of the reason these items go out so much more often is that the lending period is shorter, but it is also because this is what my community is interested in. So in this case it would be wise to realign the budget priorities to give the people what they want.

As far as books go, it is easy to see what collections are popular and which are less so. Do travel books fly off the shelves while cookbooks gather dust? Are mysteries duds, while romances have long holds queues? It’s important to look to the numbers to find out. Every library is different, and it is instructive (and really interesting) to see what patrons are actually using as opposed to what we think they are using.

The 80/20 rule can be applied to weeding as well. By looking at the 20% of titles which get the most use in any collection, librarians can begin to see use patterns emerge and can also see where the dead wood is. It can be painful to admit that the items you have been collecting for years don’t line up with patron interest, but getting rid of these items will both increase circulation and patron satisfaction with the library. The best part about the 80/20 rule is it works in reverse as well, by weeding 20% of a collection you can expect to see an 80% increase in circulation. Isn’t that worth the effort?

If you want to learn more about the 80/20 rule check out The 80/20 Principle by Richard Koch, there is probably a copy on the library shelf.