You can adjust how far back into your historical activity data that Attribution looks at attribution activities.
From the left navigation bar, go to Settings > Journey > Journey & Attribution Settings and click the Attribution Settings tab and find Demandbase activity influence time period.
Enter the number of days that you want Demandbase to look back to for Attribution. For example, if you'd like Attribution to pull all activity history within a year, enter 365.
Many companies choose between one to two years back (365 to 730 days).