The thing that I have trouble with most is referring to text boxes in the report, you do that like this:
ReportItems!myFielName.value
*** Case sensitive.
This expression, placed in a ReportItem text box Color property, displays the text in black when the value is > 0; otherwise, the value is displayed in red:
=IIF(Me.Value > 0,"Black","Red")
This expression, placed in a text box in the page header or page footer, displays the first value per page of the rendered report, for a text box named LastName:
=First(ReportItems("LastName").Value)
Edit 2/20/2017 by JoeyMorgan2012:
To get the month previous to the report month, as for a sales summary or other report for the last full month, use:
=Monthname(month(dateadd(DateInterval.Month,-1,DateTime.Today)),true)
Use False instead of True to get the full month name instead of the abbreviation. Using Year instead of Monthname will give the year and return last year for a January report. More accurate than using Year(DateTime.Today)-1