IP Australia has published a report looking at patent backlogs, inventories and pendency. 
The Report has been prepared using the same framework used by the USPTO and UK IPO.
Apparently, the number of pending applications peaked in 2009 at 100,000. By 2013, it was down to 90,000. The number of applications being filed has finally recovered to “pre-GFC” levels.
There are 278 pending applications per examiner; the lowest number since 2001. In the USA (which has a much larger number of applications) the number is 169 applications per examiner and, in the UK, 198 per examiner.
There were 26,394 applications filed in 2008. Approximately 52% passed through examination and opposition (if any) to grant. Some 9.4% were still “pending” as at May 2013.
About 20% of applications made in 2008 were the subject of a voluntary request for examination; almost all of the remainder are subject to a direction to request examination.
Almost 20% of all applications lapsed or were withdrawn when the Commissioner directs the applicant to request examination. Almost 15% lapsed or were withdrawn at the first report stage. A further 2% lapsed or were withdrawn after further reports.
950 of the applications made in 2008 (0.36%) have been subject to opposition (to date). Of those, the opposition led to only 68 (0.026%) being rejected or withdrawn.
You can read the Report here.
- Ahmer Iqbal Siddiqui, Report on patent backlogs, inventories and pendency. IP Australia Economic Research Paper 01. ?