I have a spreadsheet that contains work-categories, rates and hours for
estimating time to perform jobs.
I wish to display only the categories that have 0 hours attributed to them
in a final table, used in documentation for customers.
I have tried using advanced filtering, but to limited success. If I apply
the filter, but then later give a couples of hours work to a previously
non-used catergory, I then have to RE-apply the filter to get that row to
display.

Can you have an ACTIVE filter (i.e. if the values changes to be greater than
zero - the rows automatically become non-hidden) and if so, how do you do
this??

Thanks for your help in advance