How to get a running count based on a unique identifier

[excelmaster123_]

Hey,
I have a dataset that i need to get a running count on, based on a member_id

here is an example

MBR-ID Products Running Count
AB2021 30 30
AB2021 30 60
AB2021 30 90
AC2021 15 15
AC2021 20 35
AC2022 10 10

How can i get the result in the “Running Count” column?

 

[etaf]

=SUMIF($A$2:A2,A2,$B$2:B2)

copied down

Book1
	A	B	C
1
2	AB2021	30	30
3	AB2021	30	60
4	AB2021	30	90
5	AC2021	15	15
6	AC2021	20	35
7	AC2022	10	10
8	AC2022	10	20
Sheet1

Cell Formulas
Range	Formula
C2:C8	C2	=SUMIF($A$2:A2,A2,$B$2:B2)