It's not the easiest to find but it isnt completely hidden away either. In the CASA publications, under annual reports, appendices. The 2011-2012 report, here:
https://www.casa.gov.au/sites/g/file.../ar1112_p6.pdfhas a table going back a few years, so heres a couple.
From the 2011-2012 report:
In 2007-2008 there were 521 ATPLs issued, and 6564 current. In the same period there were 1352 CPLs issued and 4103 current.
In 2011-2012 there were 472 ATPLs issued, and 6521 current, along with 1052 CPLs issued and 3988 current.
The latest (2015-2016) report here:
https://www.casa.gov.au/book-page/ap...ing-statisticsshowed that for 2015-2016 there were 162 ATPLs issued, and 7375 current, and 1048 CPLs issued with 4616 current. Unfortunately the table from the most recent annual report also has a column for 2011-2012 showing 504 ATPLs issued and 7321 current, which is 800 different from the 2011/2012 figures given in the earlier report, so either one or the other or both is completely wrong and noone knows how many ATPL holders are active or issued in any given year. I also dont know how they classify licenceholders as current or not, and a pilot with an ATPL may have moved to a job where they only exercise the privileges of a CPL, or overseas.