Exportify can't create subtotals for you, but it is possible to get line item counts in Excel after export.

1. Select the "Lineitem name" column (for example). Filter the column from A-Z (or custom sort).

2. Select that column and head to the Data tab in Excel and choose Subtotals. 

3. The default values will create a count and display the subtotals after each "Lineitem name" column.