Fees on payments services may become a more important source of revenue growth for banks than earnings on customer balances, according to McKinsey & Company's latest Global Payments report.The global payments industry "had an extraordinary year in 2014" the McKinsey report said, "exceeding the most optimistic expectations. Revenues rose nine percent, which was double 2013's growth, climbing from US$1.5 trillion in 2013 to US$1.7 trillion in 2014."McKinsey found payments revenue was even more important to the industry over the last year."Global payments also increased its share of total bank revenue from 38 to 40 percent," the consulting firm said.McKinsey said it expected "annual global payments revenues to increase at a relatively stable annual rate of six percent during the next five years, exceeding US$2 trillion by 2020."Surging digital and mobile payments will be a feature, "with digital commerce to continue growing at twice the rate of personal consumption."This trend should, in turn, generate growth in electronic payments, which will likely accelerate, doubling card payments volume by 2019, McKinsey said.