Number of brands deferring spend has risen by eight percentage points month on month.
Porter replaces Mundipharma's Sameer Desai who previously held the WFA's top regional role.
VIDEO: Stephan Loerke of the WFA discusses the impact of GDPR, the evolving use of agencies, the group's media charter, and the biggest issue people aren't talking about enough.
TOP OF THE CHARTS: A third of those surveyed by the WFA lack more than a basic understanding, however.
Structural changes within the organisation aim to advance adoption of its Global Media Charter.
All six shortlisted CMOs have been revealed. Vote now for World Federation of Advertisers Global Marketer of the Year.
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