Validate skip_or_fill_minimum data attribute

Validate skip_or_fill_minimum data attribute

Using jQuery version 1.9.1
jQuery validate version 1.16.0
jQuery validate-additional-methods version 1.16.0

I've googled and also searched here for the correct usage to get this to work. I'm not sure how you pass the element you're wanting to "track". I've tried:
  1. <input type="text" name="billing_po" id="billing_PO" class="PO"
  2. data-rule-skip_or_fill_minimum="2"
  3. data-msg-skip_or_fill_minimum="Need to fill in both or neither"
  4. >

  5. <input type="text" name="billing_poexp" id="billing_POexp" class="PO"
  6. data-rule-skip_or_fill_minimum="2"
  7. data-msg-skip_or_fill_minimum="Need to fill in both or neither"
  8. >