Not every digital marketing metric provides the same level of insight into business performance. Exploring digital marketing KPIs helps professionals distinguish between measurements such as impressions, clicks, conversion rates, cost per acquisition, and return on investment. Each can answer a different performance question. The appropriate KPI should reflect what the campaign is intended to achieve. This makes measurement more useful for evaluating results and deciding where resources should be allocated.
http://www.uniccm.com/digital-marketing-kpis
