I am new to crystal report and I want to know how to get the sum of min of field in the date level?

here is my example:
date 1
name   qty
a    3
a    10
a    2
minimum (qty) = 2
date 2
a   4
a   6
minimum(qty) = 4
(sum of min qty in each date = 2 + 4 = 6)

I have problem to get the sum at this level?

Thanks,
Xiao
  

I have a similar problem, which is:

I have passes a shared variable through from a sub report which is a sum per group within the sub report.
On the main report I want to sum this variable at the end of each group and as a grand total at the end of the report.  I have tried using a global variable I found on another forum, but it has a couple of issues:
1. if I place it in the same section as the values from the sub report it does cumulate the figures, but if any of them = 0 from the sub report, it takes the previous value and adds it on instead of staying the same.
2. if I place it in the group footer it just gives the total of the last value from each section.
3. if I place it in the report footer it puts the total from the last entry in the first group.

The method i found on another forum was:

in the sub, in any formula (including formatting formula) add a line like so

@result
shared numbervar TotalCost := <summed val>

in the main report

@GTResultBuild
shared numbervar TotalCost;
global numbervar GTCost;
GTCost := GTCost + TotalCost;

//that lives in the next group footer down from the subreport so it always happens after the sub
 
@GTResultShow
shared numbervar TotalCost;
//this just prints it out

I have been working on this report for several weeks, on and off, and now have everything else I need on the report, apart from these group/report totals; so any help would be greatly appreciated.

regards

David