The first screen displayed on your dashboard is your total spending during the previous month. This is categorised in the chart to show spending on certain groups in relation to other groups and the total.
Swiping to the left of your screen will take you to the Spend this month chart. Similarly, this gives you a breakdown of your spending on each category, but for the current month so far.
Swiping left again will take you to the final dashboard chart which details outgoings for the current month as compared with the previous month. Small arrows pointing up indicate that spending on a certain category this month is greater than that from last month.