We propose an initial approach to minethe usage trends of libraries in Haskell, a popular functional programming language. We integrate it with a novel, initial method to automatically determine the reasons of clients for switching to different versions. Based onthese, we conduct a preliminary investigation of trends of usage in Haskelllibraries. Results suggest that trends are similar to those in the Javaecosystem and in line with Rogers' theory on the diffusion of innovation. Our results also provide indication on Haskell libraries being allby and large stable.