Collaborator Comment Pin Location - What are the units?

collab.exe admin review-xml <review#>  returns an xml structure that includes the comments.

Part of the response looks like this:

<location type="Coordinate">
<page>4</page>
<pinNumber>3</pinNumber>
<x>1030</x>
<y>669</y>
</location>

What are the units of the X and Y coordinates?