Exporting through CSV to Excel may be the best route for the moment. It looks syntactically possible to query the full set of OF tasks in Applescript (to avoid exhaustive and repeated iteration) but the results seem very buggy (see test code below)
I have submitted a report.
Code:
tell application "OmniFocus"
tell window 1
set selected view mode identifier to "project"
set focus to {}
select library of sidebar
tell content
set refLeaves to a reference to leaves
-- get total count of tasks
set intTotal to count of refLeaves
-- THIS QUERY ALMOST WORKS
set lstSubSet to refLeaves where note of value ≠ ""
set intHasNote to count of lstSubSet
set lstSubSet to refLeaves where note of value = ""
set intNoNote to count of lstSubSet
set intDiscrepancy to intTotal - (intHasNote + intNoNote)
display dialog "Gap: " & intDiscrepancy as string
-- QUERYING ON DATES GIVES COMPLETELY INCORRECT RESULTS
set lstSubSet to refLeaves where ((due date of value) is (current date))
set intToday to count of lstSubSet
set lstSubSet to refLeaves where ((due date of value) > (current date))
set intAfterToday to count of lstSubSet
set lstSubSet to refLeaves where ((due date of value) < (current date))
set intB4Today to count of lstSubSet
set intSecndDiscrepancy to intTotal - (intToday + intAfterToday + intB4Today)
display dialog "Second Gap: " & intSecndDiscrepancy as string
-- ODDEST RESULT -- Small positive number - hard to explain
set lstSubSet to refLeaves where ((due date of value) ≠ (current date))
set intOdd to count of lstSubSet
display dialog "Odd value for tasks with due date NOT today: " & intOdd as string
end tell
end tell
end tell