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Historical Bulk Traffic Estimation
This endpoint will provide you with historical monthly traffic volumes for up to 1,000 domains collected within the specified time range through October 2020. If you do not specify the range, data will be returned for the previous 12 months. Along with organic search traffic estimations, you will also get separate values for paid search, featured snippet, and local pack results.
Traffic volume is calculated as the product of CTR (click-through rate) and search volume values of all keywords the domain ranks for in a relevant category of search results (organic, paid, featured snippet, or local pack). You can learn more about how we calculate this metric in this help center article.