Zipcodes that begin with zero

[DesignMeCG]

EXPLANATION OF THE ISSUE

Importing users that have a zip code starting with zero removes the zero. For instance, zip code 04101 imports as 4101.

STEPS TO REPRODUCE THE ISSUE

I save the information as a Windows csv in excel or numbers then import the information. I also have manually copied/pasted the correctly typed information into the "import" box. Same thing - zip code with beginning zero drops to 4 digits. I have tried adding an apostrophe before the 0 - still removes that initial zero.

BEHAVIOR THAT I EXPECTED

5 digit zip code.

BEHAVIOR THAT I OBSERVED

Consistently drops the initial zero no matter what settings I use.