I see a line with a decreasing slope (decreasing because it 'ends' at the red dot... ?), but I have no context. Does a negative slope mean my inbox situation is getting better, or worse? Some sort of context would be nice.
The general idea is that the graph is of your inbox size, so a reduction in quantity (decreasing slope) would represent a "better" inbox situation. How might you suggest providing that context while keeping the ensuing image lightweight and clutter-free?
Be specific about that when describing the graph. I don't see anything about inbox size on the page. Graph is clean, informative, and immediately understandable given that crucial bit of information...
Full disclosure - i've never heard of a sparkline graph, and i'm guessing I am not unique in that.