SQL count of vacant positions in each department for the last three months

Summary

count of vacant positions for each department group by the last three months

Content

Hi,

I am trying to write a sql in BIP to get the count of active vacant positions for each department and further group them by the last 3 months when run as of the sysdate. It needs to be a BIP and not OTBI. If you have achieved this before then could you please share the SQL code? It would be a pivot table with details such as below.

	Number of Vacant Position
Department	21-Jan	20-Dec	20-Nov
Dep1	10	15	5
Dep2	12	17	7
Dep3	9	8	2
Dep4	9	9	7
Dep5	11	12	9
department Wide	51	61	30

Many thanks in advance,