frequency or countif , comparing cells in 2 ranges

Hi,
I have a sheet with three columns: "Store name", "Expected income" and "Actual income".
Each store has its own actual and expected incomes.

I want a cell to tell me how many stores in total achieved a lower than expected income.

I want to do this without adding another "difference" column.

I was thinking the formula might be along the lines of
=COUNTIF(R2C2:R11C2,"<"&R2C3:R11C3)

But this is wrong

Can anyone help me please?

x

Think I solved it myself... it's "=FREQUENCY(R2C2:R11C2-R2C3:R11C3,0)"