One of the key drivers is the huge disparities in CPMs that publishers realise when they sell directly and when remnant inventory is sold via ad networks.

关键驱动之一是发行商认识到采用按展示付费的广告（CPM）时，在他们直接销售和通过广告网络商销售存货之间存在着巨大的差异。

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And niche or remnant inventory sells for higher prices due to demand-driven pricing.

FORBES: Interactive Marketing Spend Will Near $77 Billion By 2016

We take their remnant inventory and give it a new life by shooting unique editorials as creative and beautiful as ads in the top fashion magazines.

FORBES: Connect

This has some industry observers excited about how Google will help sell radio advertising, particularly in moving so-called "remnant inventory, " those spots which aren't purchased in advance and are usually sold at steep discounts at the last minute or simply go unsold.

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