I have a need to generate an incrementing number in a list. The
number will be 0001, 0002, 0003, etc., until the change occurs on a
value in another column.

In the example below, when WYE465 changes to WYE565, the incrementing
number restarts at 0001. This needs to occur again when the value in
the first column changes to a new value ( e.g., WYE566 ).

Any assistance in creating a formula in excel that will perform this
would be greatly appreciated. Thanks.

Table:
value incrementing count
WYE465 0001
WYE565 0001
WYE565 0002
WYE565 0003
WYE565 0004
WYE565 0005
WYE565 0006
WYE565 0007
WYE565 0008
WYE565 0009
WYE565 0010
WYE565 0011
WYE565 0012
WYE566 0001