Changed ticks on x-axis to be equal the number of years. This should be removed again once the number of years becomes too large.:w
Changed the line plot into bar plots which results in a better visualisation with a small number of years (as is the case at the moment). Also fixed a bug(?) which changed the treemap of a zoomed in department back to the main treemap if the user switched between income and expenses. The treemap now stays at the same level, allowing for the nice animation of the blocks.