Tables :: Total Of Entries In Date Field

I have a simple table named [Groups] containing a Primary key ID, a Group name, a Group Leaders name and a date field. The date field merely lists the date of a particular Group related occurrence.

I need to know how many records have dates entered and assumed a simple total would achieve this. The Total is correctly shown in the appropriate row but most, but not all, of the date records are converted to show the same 'total' number.eg the date 28/01/2014 is changed to !4. Quite a weird occurrence.

Is it the case that date records cannot be totaled, in which case, why not all?