I have been recently working on another weeding and collection maintenance project. My latest client library has limited space and budget and needs a lean, mean collection that works hard for the money. As the designated "reality check" or collection consultant, I have had some interesting discussions on what does a library REALLY need to serve the community. Since we can't afford the space or the cost of throwing caution to the wind, each purchase for the collection must deliver the goods. I am going to make a wild guess that many libraries are in a similar position and need to make not just good choices, but REALLY good choices. So here is where your shelf list is a selector's best friend.
A good shelf list should contain Author, Title, barcode and date published. In addition, if you can add how many circulations each item has had and the DATE of last circulation, you have now got yourself a real party! The secret to not being overwhelmed with a list of thousands of books in one report is to divide your collection into manageable pieces. Make a report with just the reference collection or just audio books. Taking a look at small bite sizes are easier to deal with. Make priorities with collections that have a high per unit cost and start there. (For most small public libraries the more expensive collections per unit will include audio books, large print, video games and reference.) Look closely at these collections--item by item. I am lucky enough to be able to dump a shelf list into Excel and sort by anything: date published, number of circs, etc. Even a large collection can be sorted to just look at stuff with no activity or just one circulation/use. Medical or legal can be quickly sorted by date and right away you can see at a glance what might have questionable currency issues for weeding or replacement.
Now I am NOT suggesting that a dictionary has to have the same activity for library use as a video game or a current DVD, but it should have a performance expectation. I have run into libraries that have bought dictionaries like clockwork every year for DECADES without thinking that it might need to be reconsidered in light of electronic choices or use. Are cheaper paperback dictionaries a better choice for your students? How are the dictionaries being used? Can you manage by skipping a year or two and still be relevant?
Take your shelf list and divide into chunks or collections or however makes the most sense for your library. Develop an expectation of performance for a collection. Not sure where to start? Use a benchmark based on circulation period. In one library a new fiction title is circulated for 4 weeks. Just to start somewhere I guessed that could translate into 12 circulations in a year if everything was perfect. Of course not everyone adheres to circulation periods and browsing is not always perfect but if its an unknown author, start with 4 circulations in 6 months and see what happens. This isn't scientific but its a place to start.
Collection is a beast that must be tamed and managed and in tough budget times, you need to pay close attention to how your collection is actually serving your community. Old fashioned thinking of "we always buy a dictionary every year" or "we might need this someday" is not helping you with your current collection needs. Tough times need tough selection standards. Business as usual won't cut it and with a shelf list you have data to support choices. Managers: this is also a good tool for a discussion on collection priorities. Maybe in your library it has to be a discussion about less travel and more resume/career materials. Looking at the data is helpful for everyone when serious choices have to be made.