Change report to automatically select records two months prior

Summary

Automation of report selecting records two months prior

Content

I have a report that I run each month which is then sent to another department.  The purpose of the report is to select records from two months prior so it has a between prompt where I fill in the dates.  So for October I would select August 1 through August 31st.  I want to automate this report and schedule it to send to the recipient automatically.  How do I go about getting the report to look back two months and select the beginning of the month thru the end of that month.