Repeating fields as opposed to subtable

I would like to be able to include 5 iterations of several field types - activity, units, value.
The value is calculated by multiplying units by a specified rate elsehwere in the record.
The use case makes a subtable solution cumbersome and I need to merge these fields into a word document whereas sub tables can I only be merged into excel - as I understand it.
Is there a technique?