The following rules apply to the performance dashboard data retention:
Data is stored in weekly historical partitions.
Data is archived after one month.
Data is deleted after 18 months.
To change data retention times, click the Settings icon > Database Settings > Data Retention > Performance Dashboard Data.
To archive the performance data during a database backup, click the Settings icon > General Settings > Advanced Settings > Performance Dashboard and set the Add Performance tables to the backup option to yes.