Why is this formula giving me an error on blanks?

[slam]

=IF(OR(ISBLANK(B1),ISBLANK(B2),ISBLANK(B3),ISBLANK(B4),ISBLANK(B5),ISBLANK(B6),ISBLANK(B7),ISBLANK(B8)),"",IF(B1="Female",655+(4.35*B2)+(4.7*B3)-(4.7*B4),66+(6.23*B2)+(12.7*B3)-(6.8*B4)))*B8-B6

I want the result to be blank unless there are values in every every cell from B1 to B8, then if there values in each cell, i want the first calculation performed in B1 is "Female" and the second calculation performed if B1 is "Male".

The formula works perfectly when all values are entered. I'm just not having it handle the blanks correctly apparently.

B1 through B8 are a mix of data entry cells, data validation lists, and a couple of formulas.

Anyone know where I'm going wrong?

 

[slam]

Think I just figured it out myself - I had to move the last part of the calculation inside the bracket as follows:

=IF(OR(ISBLANK(B1),ISBLANK(B2),ISBLANK(B3),ISBLANK(B4),ISBLANK(B5),ISBLANK(B6),ISBLANK(B7),ISBLANK(B8)),"",IF(B1="Female",655+(4.35*B2)+(4.7*B3)-(4.7*B4),66+(6.23*B2)+(12.7*B3)-(6.8*B4))*B8-B6)

That right?