Of all the metrics we calculate with Aureum, this is one of the more straight forward approaches.


To calculate this metrics, an Invoice must be imported from an accounting or payment processing app like Quickbooks or Stripe.        


    ARPA =  Total Revenue / Total Number of Accounts (Customers)


To figure out the temporal component, we look at the Invoice date (when the invoice was sent, not when it is due). We then set a rolling metric to calculate ARPA by looking at all invoices on or before a specific date. This means to calculate ARPA this month, you use all Invoices with a date on or before the end of this month. 


Once you have those parameters, the formulas remains the same and excludes Invoices that are after a given end of month date. 


Here's an example:



#
End of Month
Total Customers
Churn Customers
Sum of Invoice Amounts
ARPA
1
2022-02-28
100
0
$1200 + $900 + $800
$29
2
2022-01-31
90
0
$900 + $800
$19
2
2021-12-31
80
0
$800
$10