The search volume for a keyword shows 6,600 searches per month (actual searches is 30). Guess which tool I'm referring to? Yeah, the title gave it away, but that's how most people use the tool. The keyword? "sugar bowl tickets" Which took place on January 1st (the 30 were probably keyword/analyzer bots) By default the Keyword Planner shows you the AVERAGE search data from the previous 12 months. No big thing in general "evergreen" niches such as weight loss, fitness, diet, etc. But for fads, trends, events (South beach Diet, Zone Diet, Super Bowl Tickets 2015, etc.) it can make a huge difference. Don't believe me? Try searching for - "super bowl tickets 2015" You can manually select specific months search results from a drop down on the left.
Micro Niches are difficult to gather keywords for regardless. It wouldn't matter which keyword tool you used. I really like the Google Keyword Planner tool.