When you Google “Follow the money,” you get more than 37 million references. It seems that most everyone understands that the money trail provides answers that weren’t obvious or previously disclosed. Most references seem political whether US or foreign. However, today businesses are adding a new dimension to the old adage and investors should be paying attention.

In this case, the money trail takes the form of spending, specifically consumer spending, which is tracked in great detail every year by the US Department of Labor through its annual Consumer Expenditure Survey (CES). The local grocery store, Home Depot, Wal-Mart and other vendors do not care at all if their clients are US citizens, legal immigrants, or part of the growing number of illegal immigrants in our society. There is no screening process for entry into a retail establishment when the consumer shows up with the money to spend.

What is changing significantly is that businesses are tapping into the resource of illegal immigrants by allowing them to use more traditional sources of capital to live as well as to work within our society. These sources include credit and bank accounts, which in turn allow the immigrants to purchase more goods and services or leverage the assets they have.

Investors should be thrilled because immigration spending has a predictable pattern. Just like our home-grown consumers, immigrant spending tends to happen in certain age-ranges. Our economy receives the benefit of the spending of all the residents of our nation, regardless of status. The level and direction of that spending is influenced by where those residents are in their life cycle. Spending patterns are identifiable whether you are single, raising a family, saving for retirement or in retirement. Demographic research and the CES conclusively demonstrate that individual or family spending at these different times in life changes dramatically.

The family stage requires the most spending, especially when offspring become teens, and therefore creates the most economic activity. This part is not “rocket science.” Every parent knows that teenagers’ needs are the most expensive part of the household budget. Whether it is their perceived need to wear designer clothes, auto insurance, or merely the food they eat. Teenagers at home drive family spending in developed economies.

The US population of teenagers will be peaking at the end of this decade. That has certain predictable consequences for their families, our economy in general, business owners and investors. When teenagers leave home to start their own, independent lives, Mom and Dad discover discretionary income in the budget. Earnings typically continue to rise for another ten years allowing parents to pay down debt and begin serious accumulation of retirement funds.

Most immigrants enter the country between 28 and 32 years old, just at the start of the family-raising years. With, on average, 20 years of increasing spending in front of them, our economy, businesses, and investors actually benefit from their residence here. It should be no surprise that spending by immigrants is similar to those of us who were born here. After all, most of them immigrate because they want to live like we do.

Paying attention to the growing or waning demographic demand for types of products allows businesses and investors to make better decisions about how best to use their capital. Unlike stock market price trends, which have absolutely no predictive value, spending trends are tied to family status and age.

For instance, the average age for a couple at their first marriage is 26.5 years. This has been increasing each decade as the education level of our population has increased. If your business caters to the various needs of a wedding, an increasing number of 26 year olds in your service area would be good for your future sales. If the number was expected to decline, you probably have a great need to revise your marketing and business plan. Similarly, an investor in a wedding services company would make a better decision if they first looked at the probable demand by examining demographics and spending data.

In addition to spending, immigrants, both legal and illegal, bring us another benefit — workers. We as a nation have a significant issue facing us as baby boomers begin to retire in record numbers after 2010 — a shrinking workforce. This issue has not received much press coverage, although Alan Greenspan has mentioned it in his reports to Congress.

Most analysts are too preoccupied with the current unemployment rate, which recently dropped to five percent. Few are looking forward and asking, “What will happen when boomers, who comprise one third of our population, begin leaving the workplace? Demographers generally start the Baby Boom in 1946. The average retirement age today is 63. The first wave of Boomer retirement officially starts in 2009. Though some have already begun retirement, we are referring to the average age. This begs the question, “Who will take their place?”

Following the Baby Boom was a Baby Bust known as GenX. There aren’t enough of them to replace the projected Boomers turning retirees. Immigration can help fill the labor force gap as Boomers retire. However, it creates a different problem as we face homeland security issues to sort out the bad guys while we need the good guys to help keep our economy running.

In the end, however, there will not be nearly enough immigrants of any status to fill what could be a long-term economic contraction and a multi-year decline in the labor force. With 290 million Americans and roughly one million immigrants entering the country each year, the math simply doesn’t work out. We still must recognize the demographic trends that are unfolding in our nation and our economy, and plan accordingly.

Remember, if there is no spending, there is no profit for either the business owner or the investor. The Consumer Expenditure Survey is full of information about where our money goes. Both businesses and investors improve their chances for profit by taking time to “Follow the Money.”

(Editor’s Note: Donald Creech is founder and president of Investor Resources, Inc., a fee for service investment advisor registered with the SEC.).