Gone are the days of considered 'hunches' in marketing.  

The wealth of data at our fingertips through tools like Google Analytics, Adwords, HubSpot and dozens (if not hundreds) more mean modern marketers can pull powerful insights from historical information to build validated marketing hypothesis to test.

For inbound marketing this is essential.  To plan for growth we need to understand the baseline metrics and determine the real real, not high level trends or guesses but black and white X and Y facts.  With these we can more accurately build in budgets and activity levels required to achieve both realistic and stretch client goals.