Excel Formula Help

Hey /prog/tards, I'm making a chart in excel right now to chart how much money I have lioncashed, and I'm trying to make a row of overall amounts. So far, I have =SUM(B5,CONCATENATE("B",COUNTA(B:B)+COUNTBLANK(B1:B5))), but the problem is, Excel puts #VALUE! in the cell and tells me there is an error. Everything calculates right up until it tries to do SUM and then it screws up. What is wrong?

I don't think it's impossible. Common sense says this should work. But excel doesn't like it. I mean, the CONCATENATE works outside of SUM. Shouldn't it do a sum with a range of B5 to whatever the other thing evaluates to?