You can add numbers to the past with the KPI module if you want to have a more extended period visible. You can also edit these numbers if you notice a mistake. In this article, you can read how to do that.
Add numbers to the past.
Click the pen icon in the KPIs tab.
Click on the arrow to go backward from the monthly list to the month you want to add numbers.
Add your numbers
Click save.
Edit numbers in the past.
Navigate to the KPI module
Click on the number you want to change (navigate back in time with the arrows)
Add new value
Click save