Found my own answer
Created field Final total as a summary and added the "total" option on it.
You can also use a calculation defined in the layout's table that does this:
Sum ( PortalTable::Field ) to add up the rows in the portal. This approach should not be used if the portal is filtered as it will ignore the filter, but will update more smoothly and quickly when a portal value is edited.
I have filtered portal row. How can I sum it?