Add forecast adjustments

You can make adjustments based on upcoming traffic pattern changes so they’re better reflected in forecasting numbers. Once you have a forecast segment, you can create a forecast adjustment based on that segment’s targeting.

1. Sign in to Google Ad Manager.
2. Click Inventory Traffic forecast.
3. Access the settings for a new forecast adjustment by doing one of the following:
   • Click the Segments or Adjustments tab, add a forecast segment, and click Add forecast adjustment. See Create a segment through the Segments or Adjustments tab above for details.
   • Click the Segments tab, click the name of a segment in the table, and then click New forecast adjustment from the segment’s details page.
4. Name the adjustment.
5. Under "Adjusted date range," select the future range of traffic that this adjustment will be applied to.
6. Under "Volume adjustment based on," select whether you want to adjust the targeted segment and date range based on:
   • Total volume: Total ad opportunities.
     1. Under "Ad opportunities," select the number of ad opportunities you want to allocate to the segment and date range.
   • Daily volume: Ad opportunities selected by day.
     1. Click Download CSV to download a file that contains the daily ad opportunities that will be allocated to the segment and adjusted date range. If you have never uploaded a CSV file, this will download a template with the current numbers. If you have uploaded a CSV file, this will download the previously uploaded file.
     2. The file has a row for each day in adjustment’s date range.
     3. Update the file with the number of impression opportunities (total, not just the adjustment) you want to allocate by day. Example: If the current number of impression opportunities is 500, and you want to add 200, you would enter 700. The file must have a row for every day in the adjustment’s date range and contain data in the format:

        2019/02/11,5000
2019/02/12,75000
2019/02/13,4000

     4. Upload the updated file back into the system: Drop it onto the "Drop file here or" box or click Browse.
   • Historical volume: Actual historical traffic.
     1. Under "Historical date range," select a date range in the past whose performance you want to apply to the adjusted date range.
     2. Under "Use targeting from," you can use the targeting from this forecast adjustment’s segment (default) or choose to select other targeting.
     3. Under "Percentage of historical volume," type the percentage of impressions from the historical date range that you want to apply to the adjusted date range.
7. Click Save.
   The new adjustment appears in the table of existing adjustments. Adjustments are usually applied within 48 hours.

See forecast adjustment details

Click the new Adjustments tab near the top of the "Traffic forecast" page, or click All segments from a segment details page. You’ll see these columns: