auto-update calculation fields in web publish mode

[dtl]

newbie here .. setting up a test file ..

I have setup some calculation fields in a form ..

in FM Pro browser mode these calculated fields change instantly when any fields referenced in calculation formulae are changed

but .. in web publish mode in localhost .. calculation fields only update when "submit" is clicked.

I would like the calculated fields to update before pressing "submit" (as they do in FM Pro browser mode)

Is there some button (or other) function I can place in the record layout to instantly update these calculated fields when other fields are changed on web site .. e.g. like F9 in Excel for manual calculation?

dtl