How many times Corrective Action (CA) has been executed one year so far ?
SQL> select CA_NAME, count(*)
from sysman.MGMT$CA_EXECUTIONS
where START_TIME>=sysdate-365
group by CA_NAME order by 1
CA_NAME COUNT(*)
---------------------------------------- ----------
...
..
.
EXTEND_TABLESPACE_NORAC 3
EXTEND_TABLESPACE_PDB 16
EXTEND_TABLESPACE_RAC 70
NON-RAC_RMAN_AUTO_BACKUP_ARCHIVELOGS 56
RMAN_AUTO_BACKUP_ARCHIVELOGS 533
...
..
.
10 rows selected.
About view MGMT$CA_EXECUTIONS , Oracle official documentation is here or just click the following link.