The algorithm used to determine a word is VERY simple (a space, tab, or return separated by anything else).

It's a green box for 0-99wpm, a gold box for 100-199wpm, and a red box for 200-299wpm. For 300+ it turns all white. No one types THAT fast, do they? The colors were used to avoid handling 3 characters in that tiny icon.

At the last minute, I added a history graph. It records the last 15 mins of typing on a graph. Double click the icon to see it, double click the graph to hide it. The graph IS resizeable even though the resize handles don't show. content_stop