How can I combine 2 columns into one?

[#1]

I would like to combine two columns into one. My data looks like the table below where "." represents missing data. I would like to make a column which resembles Column C.

Column A	Column B
.	2013
.	2014
2016	.
2017	.

Column C
2013
2014
2016
2017

[#2]

So far I have tried adding a new column with the formula: If( :Column A != "", :Column A, :Column B) but this doesn't work and I'm not sure why. It fills in the values from Column A but not from Column B.

[#3 · Accepted solution]

I'm not familiar with JMP but isn't the first condition checking if the cell in A is blank versus missing?

SAS has a keyword, missing, does JMP have the same?

ie

If(is missing(:Column A) , :Column A, :Column B)

[#4]

Thank you, I was able to get the formula to work using Is Missing().