SSRS minus first two dates as the header I have a SSRS report that has one column called startime that is listed in mm:dd:yyyy hh:mm:ss format.  For the header of this column I want to minus the first date from the second date to give me an idea of how long is between the two dates, this will likely be in minutes.

I don't need a running total, I just need to be able to minus the first date from the second date in the column will be good enough.  I have bee playing around with the following but its throwing up some strange results.

=Fields!StartTime.Value - Previous(Fields!StartTime.Value)


Does anyone have any ideas?

Thanks
Can you do the calculations in the dataset the report uses? May have an easier time doing that then building the expression needed to calculate the column for SSRS