To assure that the Library's collection is organized and easily navigable, librarians regularly carry out a weeding procedure to remove items according to certain criteria. These criteria may include but are not limited to: low circulation rates, containing outdated information, degraded in physical quality, and no longer fitting into the Library's collection-building policy.

These days (and for some time) our shelving volunteers are constantly mentioning the lack of space to shelve books in certain collections. Some examples are Fiction, Social Sciences, Psychology & Philosophy.

I’m trying to weed as much as possible, going like a fireman from collection to collection and putting down fires (meaning freeing up space), but it seems like I’m fighting a never ending battle. I clear one space and the next day I get notified that there is another place that is in problem.

But what are the overall statistics of adding books vs weeding them in the Library? Every month I’m collecting statistics about added and weeded books by collections so in this text I will try to analyze the data, and the result will hopefully give me more insight for the next steps in this project.

Data used is concerning adult collections and using the data from 2018 until 2021.

Year 2021 2020 2019 2018
Added 2180 2175 2519 2055
Weeded 1254 1716 3383 476

As we can see in the table, in all the years we added more books that we removed, except in 2019. In this text I will not talk about the individual collections so I cannot be 100 percent sure, but I believe that the weeding was not done equally, but was done in certain collections (if my memory serves me, it’s the Literature collection that got heavily weeded in 2019).

When we sum up the numbers for the period 2018-2021 we can see that we added 8929 books and removed 6829. This equals to 2100 more books added than weeded. Written in percentages, we added 13.4% more books than we weeded.


This is an alarming situation because we have a limited amount of space and it’s obviously filling up. What should we do?

First step would be to equal the numbers of books so that we add and weed the same or similar number of books each year. 2100 books is a lot and I don’t think that it’s a short term possibility. It will take a lot of time to weed that amount of books. So I propose to focus on current year, and try to make it 50/50.

What are the stats for the half of 2022?

Added 974
Weeded 613

So far we are losing the battle. We added 22.8% more books than we weeded. It’s time to make a battle plan. In average, we added 163 books each month this year. This means we need to weed 163 plus 60 books so we can catch up to the beginning of the year. Ideal, it would mean that we have to weed 224 books per month to finish 2022 equally. To put it into a perspective, if I work 20 days a month, this means I should weed 11.2 books per day. I think that’s possible.

Second step would be to make sure that more books are weeded in each collection than added so that there would be a space for new arrivals until the next weeding circle. So this step is more local, the amount of books would vary depending on the collection, but we could say that there should be 5% more weeded books than added. The first number could come from the last years acquisition and adjust by observing the number of added books in the current year. For example, in 2021 we added 69 books in the Philosophy & Psychology collection. Until June 2022 we added 30 books in this collection. So we can keep the bigger number from last year. If my calculations are correct, 5% of 69 is 3.45. This means that we should weed 73 books and this, in theory, should keep our shelves from overflowing and leave some space for new arrivals.

Since we didn’t weed some collections for a long time, following the specific criteria we should weed as much as needed so the collections would be trimmed to their useful and needed size. So 5% is minimum, but it can go more if needed.

Weeding 5% more books than adding would be done once and the third step would be to always weed the same amount of books as added in the last year. In that way we would always keep the shelves tidy and the collections would not grow wild, but we would have control over it.

After this we should be weeding of all our collections annually and regularly. That’s a massive objective, and I’m not sure how long it will take us to come to this stage.

Battle Plan

Here is the battle plan!

1. Weed the same amount of books as added

Objective: weed 224 books per month which means 11.2 books per day.

2. When working on a collection make sure to weed at least 5% more than it was added last year

Objective example: Weed 73 books in Philosophy & Psychology sections

3. Keep on weeding regularly and keep the number of added and weeded books in each collection the same or similar.