Crystal Reports chart

I have a report That list phone calls that are received by users. These calls are grouped by user, then by Month, week, day and hour. I want to make a chart that shows the calls by day of week (Sunday, Monday, Tuesday, etc) and this chart will be in the footer of the user group ( The chart will show the total calls that were recieved in each day of the week by that user).

The way i have done it was: In the Data tab of the "Chart Expert" option "Placement - Place chart:" i selected the "for each" user group (This is the first group).

In the option "On change of" i put FF_GetWeekday
(a formula field to get the day of the week")

In the option "Show values" i selected the field "table.call_id" to count all the calls that were recieved in each day of the week by each user. This works fine, the problem is that i need to count only the calls that were answered (without the lost calls) by the user and with a call duration greater than 0 seconds.
The chart expert dont have any option to validate the counting of the calls.

I have tried instead of the field "table.call_id", using a formula field with a code something like:
If table.call_duration>0 and table.call_type="Answered" then "{table.call_id}"
but the result is always the correct+1, for example if i have 30 calls in monday for user "USER1" then in the chart appears 31

I dont know what i am doing wrong or if what i am trying to do is possible.

can you help me?

Thank YouSounds to me as if you need to "reset" ( to zero) the value of the formula field ("{table.call_id}") each time you begin a new group, a new user.

Or try a running total where you want to evaluate when
table.call_duration>0 and table.call_type="Answered" and reset on user.