Nothing makes marketers' ears perk up more than the words "untapped market." 

Add the sound bite that it accounts for 16.3% of the United States population, roughly some 50 million people, representing the largest and fastest growing minority group and it's no wonder credit unions have been trying to figure out ways to serve the Hispanic market.

"The credit union industry as a whole is facing a big challenge of lack of growth or stagnant growth. So when one out of six people is Hispanic and while studies point to different numbers, but it's estimated that roughly 50% of Hispanics is underserved or underbanked — that's a pretty big opportunity for growth," said Miriam De Dios, vice president of Coopera Consulting, a subsidiary of the Iowa Credit Union League and a CUNA strategic partner that specializes in the emerging Hispanic market.