sql server reporting services:

u can use the RowNumber function..
The following code example provides a running count of rows in the outermost
data region:

RowNumber(Nothing)

put it in the textbox u want in the data region.
if u have the rs books online help, check out this page:
ms-help://MS.RSBOL80.1033/RSCREATE/htm/rcr_creating_expressions_v1_3quq.htm

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