Sum rows in Excel with the same text value until sum of other column = 0 -

i trying sum 1 column of numbers in excel same text value in column until sum of values in column c = 0. here example:

           b        c          d 1  issue   action quantity      net  2  nflx     buy       25      amount 3  nflx     sell     -25      amount 4  nflx     buy       50      amount 5  nflx     sell     -25      amount 6  nflx     sell     -25      amount 7  nflx     buy       50      amount 8  amzn     buy       50      amount 9  amzn     sell     -50      amount 

what want sum column d if value of column same until sum of column c zero. know can use sumif sum column d same values of column a. not sure how include condition sum of values in column c row above = 0. summing stop reaches 0.

in example above, sum rows 2-3, rows 4-7, rows 8-9.

put formula in d2:

=sumif($a$2:$a2,a2,$c$2:$c2) 

and copy down.