Adding a custom formula field from sub-forms

Adding a custom formula field from sub-forms

I have used my 5 Aggregated Sum fields in the subform. I have another column I want to add a summary of. This can be in a separate section/field. The formula field won't pull in information from the sub-form. How do I pull information from the sub-form into the field? 

I found this, but is there a way to do it without coding?
Fetching and using field values from Subform in Zoho CRM