You can find the number of spam complaints made for each message by running an Email Messages report in Report Writer. Make the following additional configurations:
  1. On step 2. Select Columns, select Spam Complaint Rate (%) and Spam Complaints
  2. On step 5. Configure Filters, follow the steps below:
    • Click Edit next to Email Campaigns
    • Click more...
    • Select the desired campaigns, or select all of them
    • Click Apply
    • Click Save this filter
    • Click Create a filter
    • From the top dropdown menu, select Email Performance Statistics
    • From the bottom dropdown menu, select Send Started Date
    • To the right, select In Custom Range or In Predefined Range
    • Make your desired date selections and click Add this filter
Note that complaints from Yahoo domains are not included, as outlined here: Does Luminate receive spam complaints from Yahoo Feedback Loop?