Formatting calculated query result

[doma23]

I have a query that looks like this:

x: 
IIf([qry-2008]![AC]="0";"n/m";
(
[qry-2009]![AC]
/
[qry-2008]![AC]-1)*100*100 & "bp"
)

The first line of code "iif" is used to check if denominator is a zero.
First - I've put the zero in quotatian marks as without them I get "data type mismatch" error. Why is that?

Second - the overall result is something like "123.123456 bp".
What I would like to do is to format this number to ignore all the numbers after decimal point, to this "123bp".
How can I do that?
Thank you!

[doma23]

Unfortunately, there is another problem.
I'm extracting this data to excel, but because of "n/m" (non measurable) in the code, it puts the numbers as a string and I can't format them at all.
One of the solutions could be to use "null" instead of "n/m", but i still need to add this "n/m" somehow (automatically) ...?