Visualisation – decline in interest rates

There’s an interesting post at PTS Blog about a chart used in the WSJ to show the decline in interest rates. There are some issues with the visualisation but I think the bigger problem is with using a very selective dataset which may serve more to support the writer’s position rather than reflecting reality. I left some remarks on the blog but here’s a very rough-and-ready view of 3 banks’ rates using a longer time-frame. The past few months do show rapid decline, but set against a different starting point back in 2004, the overall drop is somewhat less significant than the original chart makes out.