If you want to predict the future with accuracy, only one crystal ball will do: people, by the numbers. By looking at demographics, we can predict the future. From commercial to social to political to cultural trends, counting people reveals what will trend in the next ten years. That's because it's based on what people are really doing, from fertility to location to aging.

For instance: women are on the rise in the workforce, shattering glass ceilings. Meanwhile, Generation Y -- the largest generation in history -- is going to be moving into their own homes. These are but two of the key changes that will determine fortunes and futures in the next ten years.

Want to get ahead in your field? Pay attention to these seven trends:

1. Women: On the Move

2. Immigration: On the Rise

3. Housing: A Shortage Looms

4. Education: More Students and Different Classrooms

5. Healthcare: An Oncoming Tidal Wave

6. Cars: Waning Market Demand

7. Trucking & Shipping: Strained to the Limits

The truth is, most people don't count people, even at the most basic levels. And have no idea that there are 320 million or so of us living in the United States as of now. That knowledge gap translates into many realms: marketers who don't know how many consumers there are in specific markets; city planners who don't know how many housing units to build for the next decade; manufacturers who don't scale operations to meet rising demands. There are countless questions to ask -- and the answers as well as the upsides can be found in real numbers. As waves of generations are born and age, that's what determines our fortunes, and our futures. With so much at stake, it pays to know, not guess.