[ARM \ ERPi] Null values after a data load

We have a few reconciliations that contain a "null" value (would be nice to be able to sort on these, but exporting to excel works just as good!).  However, we didn't receive any invalid mapping errors.  In order for this to happen, we probably have profiles that don't have a corresponding ERPi mappings OR there is simply no data.  Is that a correct assumption? 
We're in the process of consolidating our ERP, in some cases many accounts to one, many companies to one, etc, and we've discovered several cases where we have a null value, even though the mappings appears to be legit in ERPi.