Show value 0 in blanks fields
 

Hi,
I have the following field:
PERIODS: "PERIOD" & "" & " " & [PERIOD], which works fine.

But I want to put a Zero (0), where there is no data. I
tried PERIODS: "PERIOD" & "" & " " & Nz([PERIOD],"0")
But doesn't seem to work.
Am I doing something wrong?

Please advise any info.

Thank you,
Juan