Fields missing in import templates

Hi

I'm looking into using the Templates for Data Import in CRM 2013. I exported the template for Account. At first glance it looks OK. But when you dive into the details you start noticing that standard fields are missing. Ex. the Account Rating field. I compared the field to other fields of similar type (ex. Category) which are included in the template. I used the Metadata Browser. I was not able to see any difference. I tried adding a custom field. That was included without any problems.

So my question is. What determines if a field is included in the Import template?