Why a campaign is or is not delivering, from the DSP's own auction
report: the auction requests it passed on and why, how it did by site,
device, creative and size, and the impressions the DSP filtered out.

These numbers come from the DSP's report, so they can differ slightly
from the delivery counts on /performance, which come from our own
event files. Days are Pacific time, the DSP's own. A section the DSP did
not report for the range is null, never an empty list.

Default date range is the last 30 days.