COLUMBIA, Md.--(BUSINESS WIRE)--Merkle (www.merkleinc.com), a leading technology-enabled, data-driven performance marketing agency, announced its prominent ranking in Advertising Age’s annual agency report. Coming off of a strong 2014 where Merkle reported more than $448 million in gross revenue, the Agency Report 2015 shows Merkle is experiencing the fastest overall growth in worldwide CRM and is listed as one of the fastest-growing search and digital agencies. Merkle also improved its ranking