Adjust forecasts for special traffic patterns

Manually adjust forecasts to account for new content or special events

Note: This feature is currently in beta release to a few customers.

DFP uses the 28 previous days of traffic to determine forecasting numbers. This is fine if you have consistent traffic throughout the year, and you’re not creating a lot of new content. However, what if parts of your website or app have traffic patterns that aren’t captured in the 28-day cycle because you created new content, or you have traffic spikes during events that happen more than 28 days apart (for example, a yearly sports tournament or a semi-annual sale)?

With Forecast adjustments, you can make changes so traffic patterns are better reflected in forecasting numbers:

  • For display ads, you can make either a fixed or historical adjustment. Fixed adjustments are good for new ad units that don’t yet have a history, while fixed and historical adjustments can both be useful for existing ad units that are affected by special events. In either case, you’re adjusting the impressions that will be used to calculate the forecasting for a specific inventory. For example, the inventory will receive fixed number of 500,000 impressions, or it will have 120% of the impressions from historical traffic over a specific date range.
  • For video content, publishers often use the videos themselves to organize inventory, regardless of where on the site or app the videos play. Therefore, adjustments for video are based on video views instead of impressions. You specify a fixed number of video views for a selection of video content, custom targeting key/values, and content bundles. Note that we don’t support historical adjustments for video views.

Only some of the criteria used to calculate forecasting numbers is adjustable, while others can’t be changed:

  • Examples of adjustable criteria: Impressions, ad unit, and ad size for display ads; video views, video content, and content bundles for videos.
  • Examples of non-adjustable criteria: Time of day; number of ad units or videos on a page.

Although you can narrow down your adjustments to specific ad unit sizes, we recommend that you do so only when necessary. The more specific you get with your adjustments, the more moving parts you're introducing into the forecast, which slows down all queries for the network.

Also, it's important to note that DFP does not support overlapping forecasting adjustments. This includes any two or more adjustments that can affect the same impression. Make sure you don't add an adjustment that will overlap with another.

Read the following sections to learn more about fixed adjustments you can make for display ads and videos, historical adjustments you can apply to display ads, and additional factors that can affect forecasting numbers.

Fixed adjustments for display ads

Fixed adjustments are typically used for new ad units that do not yet have a history, or for existing ad units that have special events that may affect traffic. You can, however, adjust the forecast for any ad unit, regardless of how new it is or whether there is a change in its traffic.

To successfully sell a new ad unit, you need to know how many impressions it will receive. You know that the content of the web page on which the ad unit is placed closely resembles the content of another existing web page. You expect the new web page will have a very similar traffic pattern. You decide to apply a fixed adjustment to the forecast for the new ad unit for the first 28 days until DFP can build its 28-day sample.

To do this, you can run an ad unit report for the past 28 days on the existing ad units and use it to estimate how many impressions the new ad unit will need.

To create a fixed adjustment for ad units:

  1. From the Inventory tab, click Forecast adjustments in the left nav, and then click New adjustment near the top of the page.
  2. Enter a name for the adjustment.
  3. From the "Type" dropdown, keep the default value of Ad unit.
  4. Enter the ad units you're adjusting.
  5. In the "Future date range" fields, select the period over which the adjustment will be applied.
  6. Next to "Adjustment", keep the default selection of Fixed.
  7. In the "Sizes" drop-down, select whether you want to adjust all ad sizes allowed by the ad unit, a single size, or sets of sizes. If you want:
    • All sizes: Keep the default selection of Adjust all sizes and enter the amount of impressions in the "Impressions" box.
    • A single size or a selection of sizes: Select Adjust specific sizes from the drop-down, select a size or size set in the box on the left, and enter the amount of impressions in the "Impressions" box.
    Click + Add size adjustment set if you want to adjust additional sizes, either individually or as part of a size set.
    If you don't enter any ad sizes, the forecasting simulation assumes that impressions are distributed among different ad sizes in the same proportions as they were served during the previous 28 days.
  8. The "Impressions" box from step 7 defaults to distributing the total number of impressions, but you can change it to per day. If you select:
    • Total: The system distributes the number of impressions over the adjustment period entered next to "Future date range".
      For example, if you enter 100,000 impressions total over time for the month of January, then DFP will assume 100,000 total impressions for all of January, and the forecasting sample will distribute that total among the 31 days.
    • Per day: The system adjusts the daily total for each day of the adjustment period.
      For example, if you enter 3,000 impressions per day for the month of January, then DFP will assume 3,000 impressions per day, or a total of 93,000 impressions for the month (3,000 x 31 days in January).
  9. Click Save.
    Forecasts will start reflecting the adjusted quantity in about 30 minutes.
Understanding multiple size ad tags and adjustments

Imagine you have a leaderboard on your site that's always 728x90, and a right-hand box on a multi-size ad tag that can be either 300x600 or 300x300. If you’re expecting an increase of 100,000 impressions for that page, you'd make two different adjustments:

  • one with the 728x90 on its own line with an adjustment of 100,000, and

  • one with the 300x600 and 300x300 in the same box, with an adjustment of 100,000.

When you adjust for multi-sized ad tags, you tell our forecasting system that you expect the traffic increase to come from some combination of the sizes you specify. That means that if you enter an adjustment for 100,000 for two sizes in a multiple-size ad unit, you're telling the forecasting system, "We expect 100,000 ad requests that simultaneously allow 300x600 or 300x300 sizes.”

If, after you’ve made the above adjustment, you run a forecast for a 300x300 ad size, the forecast returns a result of 100,000 available impressions; if you run a forecast for 300x600, you'll also get back 100,000. If you run a forecast for 300x600 OR 300x300 you still get 100,000, not 200,000—because the requests won't be double-counted.

Fixed adjustments for videos

Video publishers often organize their inventory to take advantage of video content awareness. Instead of relying on the site or app structure, publishers use the videos themselves to organize the inventory -- regardless of where the videos actually play, or what the video size is. Therefore, adjustments for video are based on video views.

What’s a video view? A video view is counted when a video starts. The entire video does not need to be watched for it to count as a view.

You can select a fixed number of video views for a targeted selection of individual video content, custom targeting key/values, and content bundles.

Here’s an example of when you’d want to use a fixed adjustment for video: You have a goal of 200,000 views for the first episode of a new show. You would create a fixed adjustment for video content, set up your targeting as desired, and enter 200,000 in the “Video views” field.

To create a fixed adjustment for videos:

  1. From the Inventory tab, click Forecast adjustments in the left nav, and then click New adjustment near the top of the page.
  2. Enter a name for the adjustment.
  3. From the “Type” dropdown, select Video content.
  4. In the “Video content” section that appears, include the video content, bundles, metadata, and custom criteria that you want to base the forecast on.
    You can select bundles and metadata by clicking Video content in the leftmost column of the table. Options for Bundles and Metadata then appear in the middle column.
  5. In the “Future date range” fields, select the period over which the adjustment will be applied.
  6. Next to “Adjustment”, enter the number of video views you want applied to the forecasting numbers, and select how you want them distributed.
    • Total (default): The system distributes the number of video views over the adjustment period entered next to “Future date range.”
      For example, if you enter 100,000 video views total over time for the month of January, DFP will assume 100,000 total video views for all of January, and the forecasting sample will distribute that total among the 31 days.
    • Per day: The system adjusts the daily total for each day of the adjustment period.
      For example, if you enter 3,000 video views per day for the month of January, DFP will assume 3,000 video views, or a total of 93,000 video views for the month (3,000 x 31 days in January).
  7. Click Save.
    Forecasts will start reflecting the adjusted quantity in about 30 minutes.

Historical adjustments for display ads

There are times when anticipated changes in traffic, perhaps for an event similar to one that happened a year ago, are not reflected in the 28-day sample. You can adjust the forecast of upcoming events by creating a historical adjustment. Historical adjustments combine the impression data from the selected past time period with ad request data distributed by ad size over the last 28 days, and apply that to the upcoming event.

Example of using an historical adjustment

Let's say that your website is about the travel industry and you're booking inventory for summer travel a few months in advance. You know that your traffic will skyrocket four weeks before the start of summer and you fear that if you only rely on the 28-day sample to book inventory, DFP may underestimate the amount available. You can use a historical adjustment to base this year's forecast on last year's summer travel season.

Additionally, you know that overall impression levels for your web site have been increasing since last year. You can enter a percentage of the historic total or trend over time in your adjustment to account for the increase. For instance, if your traffic has been increasing by 20%, you can adjust the forecast by 120%.

To create an historical adjustment for ad units:

  1. From the Inventory tab, click Forecast adjustments in the left nav, and then click New adjustment near the top of the page.
  2. Enter a name for the adjustment.
  3. From the "Type" dropdown, keep the default value of Ad unit.
  4. Enter the ad units you're adjusting.
  5. In the "Future date range" fields, select the period over which the adjustment will be applied.
  6. Next to "Adjustment", select Historical.
  7. Select the start date of the "Historical date range" you want to use for the sample.
    • The date range can start up to 18 months in the past if your network has data going that far back.
    • The end date of the range will be automatically selected to cover the same number of days as the future date range.
  8. In the "Sizes" drop-down, select whether you want to adjust all ad sizes allowed by the ad unit, a single size, or sets of sizes. If you want:
    • All sizes: Keep the default selection of Adjust all sizes and enter the percentage of historic total in the "Percentage of impressions" box (learn more about this percentage in step 9).
    • A single size or a selection of sizes: Select Adjust specific sizes from the drop-down, select a size or size set in the box on the left, and enter the percentage of impressions.
    Click + Add size adjustment set if you want to adjust additional sizes, either individually or as part of a size set.
    If you don't enter any ad sizes, the forecasting simulation assumes that impressions are distributed among different ad sizes in the same proportions as they were served during the previous 28 days.
  9. In the "Percentage of impressions" box from step 8, enter the percentage of total impressions from the historical period that you want to spread out, on a week-by-week basis, over the adjustment period.
    For non-adjustable criteria, forecasting uses the last 28 days of history to scale impression data.
  10. Click Save.
    Forecasts will start reflecting the adjusted quantity in about 30 minutes.

Additional factors

There are a variety of factors that can affect how adjustments will change the forecasting numbers, including the following:

Adjustments by ad size

When adjustments are applied by size:

  • The forecast uses the percentage entered for each size and applies that to the total delivery from the historic period.

  • If the adjustment includes sizes that were added using both the single size and multiple size options, but not all possible sizes are adjusted, this actually alerts the system to increase the forecast.

Here’s an example:

  1. A publisher delivered a total of 60,000,000 impressions during the historic period.

  2. One adjustment with two sizes is entered:

    • 728x90 single-size adjustment of 15%
    • 728x90 and 970x66 multi-size adjustment of 80%

  3. The forecast will be approximately 57,000,000 impressions, calculated by the following:

    • (60,000,000 * .15) + (60,000,000 * .80) = 57,000,000

For multi-size ad units, you need to explicitly enter the adjusted impressions per eligible ad size. For example, if the ad tag has sz=300x250, 300x600, then enter one adjustment that includes both sizes. Failure to do so can inflate forecast results because the simulation adds natively forecast impressions to any sizes you don’t explicitly adjust. In this example, that means if you enter 1000 impressions only for the 300x250 ad size, the simulation would add an adjustment according to the 28-day sample file for the 300x600 size. If the sample called for 2000 impressions, the total would be 3000 for that ad unit.

Forecast adjustments set on a per-size basis: When you adjust a multi-size ad unit on a per-size basis, forecasts for ad sizes added after the adjustment use the standard 28-day sample, and existing per-size adjustments are not affected by the addition of the new ad size. Likewise, if an adjusted ad size is removed, its adjustment is removed with it.

Example: ad size added to an adjusted ad unit that’s also adjusted by size.

Sports (adjusted ad unit)
  • 728x90 (is set to 50% of total)
  • 300x250 (is set to 50% of total)
  • 160x600 (created after the adjustment -- forecast is based on the standard 28-day sample)

Forecast adjustments set only on the ad unit level: If no per-size adjustment are made, then the standard 28-day sample is used to derive impression data for additional ad sizes.

Example: ad size added to an adjusted ad unit that’s not adjusted by size.

Sports (adjusted ad unit)
  • 728x90 (determined by 28-day sample)
  • 300x250 (determined by 28-day sample)
  • 160x600 (created after the adjustment -- determined by 28-day sample)
Counteracting adjustments

You'll generally make a manual adjustment because you're expecting a change in traffic volume due to a specific event. Keep in mind that the actual spike (or dip) in traffic will be included in the 28-day sample file, and so you might need to make an additional manual adjustment to counteract that spike's (or dip's) effect on the sample's rolling average.

Here's a scenario: you create an adjustment for a week-long sporting event, which you surmise will bring an extra 10,000 impressions per day to your site, in addition to the average of 5,000 per day, for a total of 15,000 impressions per day (the adjustment). The event comes to pass and brings an average of 8,000 extra impressions per day (for a total of 13,000 per day) for that week. If you were to run a forecast for the following week, the 28-day sample on which the forecast is based includes those extra 8,000 impressions per day. This would cause the forecast results to inflate the amount of inventory that's available in the coming weeks. To remedy this, create a manual adjustment that counteracts the effect the event has on the sample file.

In this scenario, four weeks of daily data would be:

5,000 + 5,000 + 5,000 + 13,000 = 28,000 / 4 = 7,000
impressions per day on average. So you'd want to create a manual adjustment of 5,000 impressions per day if you're not expecting any other events.

 

Maximum number of adjustments

The number of adjustments that your network can store at any one time is constrained by a maximum number of ad unit days, adjustment count, and impressions. Once you’ve reached the maximum number of adjustments, the system does not allow you to save new adjustments. As a remedy, you can delete existing adjustments, or lower the number of impressions or days for existing adjustments. Note that the limits below apply to the sum of historical and manual adjustments.

The system won’t let you enter forecast adjustments once any of the following limits have been reached in your network:

  • Max number of adjustments: 250,000
  • Max number of future days x adjusted ad units: 250,000
  • On any given day, the number of target impressions for the adjustments that are in effect exceeds the cap. The cap is calculated by: 10 x (over the past 28 days, the max number of ad requests the network as a whole had on a single day)

Multiplier: each size override multiplies the days and count for that adjustment. The multiplier is applied prior to the calculation of the max single-day impression count.

Example of breaching the max number of daily impressions

  • The highest daily requests for your network during the last 28 days was 1,000.
  • You create an adjustment for 9,000 requests for April 15th.
  • You create a second adjustment of 1,100 requests per day for the month of April, which the system rejects.

Reason for rejection:

  • The max number of daily adjustment requests is 10 x (max ad requests in the last 28 days) = 10 x 1000 = 10,000 impressions per day.
  • The adjustment of 9,000 impressions for April 15th allows for an additional adjustment of up to 1,000 impressions for that day.
  • Therefore, the attempted adjustment of 1,100 per day is 100 impressions too many for April 15th.

Solution: Change the adjustments so that the total for April 15th is less than or equal to 10,000.

If the above example were an historical basis rule, the adjustment impression count would be determined by the historical basis of the adjustment. If the basis time period had more than 10,000 impressions per day, the system would reject the historical basis rule. You would then need to select a different basis period with fewer impressions.
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