your select statement for all records for 1 year would be something like:
(isnull({Master.CompleteDate}) or {Master.CompleteDate} in
dateserial(year(currentdate)-1,month(currentdate)-1,1) to dateserial(year(currentdate),month(currentdate),1-1)) and
{Master.SubmitDate}<=dateserial(year(currentdate),month(currentdate),1-1)
Then you can make 12 Running Totals
Name=MOnth1
Field to summarize=Master.masterID
Type of SUmmary=DistinctCount
Evaluate=Use a formula
(isnull({Master.CompleteDate}) or {Master.CompleteDate} in
dateserial(year(currentdate),month(currentdate)-2,1) to dateserial(year(currentdate),month(currentdate),1-1)) and
{Master.SubmitDate}<=dateserial(year(currentdate),month(currentdate),1-1)
Reset=Never
place in report footer
YOu can label the RT usning a formula
monthname(month(dateadd('m',-1,{currentdate})))
Do another running total called month2 the same way but change your evaluate formula to look at the 2 months ago...
(isnull({Master.CompleteDate}) or {Master.CompleteDate} in
dateserial(year(currentdate),month(currentdate)-3,1) to dateserial(year(currentdate),month(currentdate)-1,1-1)) and
{Master.SubmitDate}<=dateserial(year(currentdate),month(currentdate)-1,1-1)
label formula as
monthname(month(dateadd('m',-2,{currentdate})))
And so on for all 12