Redmine

I need it very much to be able to see the sum of all estimated hours right on the top of the custom query list.
The same as we can see in Roadmap/Version > Time Tracking field - but recalculated for every query I make..

Can somebody say how to code that?
For example in version/time tracking it's made like this:

<%= html_hours(lwr(:label_f_hour, @version.estimated_hours)) %>

I'd like something like this (like an example):

<%= html_hours(lwr(:label_f_hour, @query.estimated_hours)) %>

I suppose there must be something written in query_controllers.rb or so..

Unfortunately, my Ruby and general programming knowledge doesn't allow to cope with that myself..
Please help! :-)

P.S.
My first post here.. Redmine ROCKS!! THANK YOU VERY MUCH!