excel - How to sum client totals across subsidiaries when # of subsidiaries varies? -

right have client , subsidiary info in 1 column , have column filtered clients only. in column b have amount bought. want sum these amounts in column c, because each client has diff # of subsids must manually

               b      c 1    2   client           =sum(b3:b6) 3     -stuff    $$$ 4     -stuff    $$$ 5     -stuff    $$$ 6     -stuff    $$$ 7   client b           =sum(b8:b43) 8     -stuff    $$$ ... 43    -stuff    $$$ 44  client c           =sum(b45:b58) 45    -stuff    $$$ ... 58    -stuff    $$$ 

if there set distance between each client level write formula , drag down, varying number of subsidiaries means have manually. there's 150 clients don't mind doing manually it's waste of time if there's more efficient method, , have more assignments in future.

my recommendation seperate client , subsidiary 2 columns data looks this:

then can create pivot table. (insert > pivot table) here screenshot of pivot table finalized criteria off right: