Hello

I can suggest a workaround to get the statistics of the articles in the
sharepoint.
Insert a text field on the form and put a function on this text box to get
the count of the articles from the repeating field and also promote this text
field to sharepoint.

For Eg: Put this formula in the default value for text box <count(field2)>
where field2 is your repeating field.

This text box will give the number of the articles and the dropdown field
gives you the list of articles as usual.

Hope this will help you.