Monthly Recurring Revenue (MRR) is very similar to ARPA. The key difference is the temporal factor. 


In ARPA, we look at all invoices on or before a specific date.

In MRR, we look at all invoices between two dates. Specifically, between the first date of the month and the last day of the month. 


Let's see an example:


Here is the info from our ARPA 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


Here is the same data, but arranged for MRR:


#
Month Range
Invoiced This Month
Sum of Invoice Amounts
MRR
1
2022-02-01 - 2022-02-28
100
$1200
$12
2
2022-01-01 - 2022-01-31
90
$900
$10
2
2021-12-01 - 2021-12-31
80
$800
$10