Running total field gives options for Min, Max, etc. but not Sum

I wants to design Crystal Reports as follow

Name //(Group)

Date                   Amount

12/04/2010             100  

12/05/2010      开发者_如何学编程       200

Total….                300

But there are problem on insert Running Total summarize by change of group fields.

I have tried by right clicking on field Insert + Running Total. But there are no option of

Sum in Type of Summery. There are following option :

Type of Summery

Maximum

Minimum

Count

Distinct count

Nth largest

Nth smallest

How can I add/minus/multiply Group Wise ?.

Convert the Datatype of Amount column into an integer type and check with database again. In crystal reports the sum will appear only to the number fields and as your post says the Maximum, Minimum, Count, Distinct count, Nth Largest, Nth Smallest will comes only for varchars. check crystal Syntax