Republican presidential candidate Dr. Ben Carson came out swinging at the Obama administration during his May 4 candidacy announcement in Detroit. Speaking to a crowd of supporters, Carson attacked the Obama administration's economic and unemployment numbers as made up and inconsistent with reality:

"Many of these people buy -- hook, line and sinker -- the idea that our economy is getting much better and that the unemployment rate is down to 5.5 percent. You know what? If the unemployment rate was down to 5.5 percent, our economy would be humming... You have to look at the labor force participation rate."  -- Ben Carson, 5/4/2015

Carson is correct on two points: Government statistics are based solely on their arbitrary definitions and we are at a 37-year slump in the labor force participation rate. But looking a bit deeper reveals a much harsher reality.

What's Behind the Definitions

The government could make the unemployment rate 100-percent or 0-percent instantaneously, just by changing the definition of what it means to be unemployed, and this is always where great caution comes into analyzing governmental data.

By definition, unemployment in the U.S. is:

Persons aged 16 years and older who had no employment during the reference week, were available for work, except for temporary illness, and had made specific efforts to find employment sometime during the 4-week period ending with the reference week. Persons who were waiting to be recalled to a job from which they had been laid off need not have been looking for work to be classified as unemployed.

Excluded from the unemployment numbers are:

• People who are underemployed;
• People who are disabled;
• People who are retired;
• People who are full-time students without jobs; and/or
• People who are discouraged and quit looking for work.

The labor force in the U.S. is defined as:

The labor force includes all persons classified as employed or unemployed in accordance with the definitions contained in this glossary;

and the labor force participation rate is:

The labor force as a percent of the civilian noninstitutional population.

Each election cycle the two major parties take swipes at each other for taking "liberties" with the definitions of what it means to be employed and unemployed. Yet these are definitions that have been relatively unchanged since the Labor Department began collecting data.

The Harsh Reality of Ben Carson's Unemployment Math is...

Ben Carson was arguably one of the United State's greatest neurosurgeons during his illustrious career, but he's not a very good mathematician or economist.

It is mathematically impossible to totally discredit one measurement as completely unreliable and false, and then tout another that has the first measurement embedded in its calculation.

Carson could have addressed the chronically underemployed or discouraged workers, and would have had a message that rang true with many voters. Carson could have addressed the fact that most of the jobs that have been created during the recovery have been lower-paying service jobs, while traditionally higher paying jobs are still unavailable -- and would have had a message that many voters already intuitively know.

But instead, he chose a measurement that is only really telling us something we've expected for a generation: the "over 55" category in the labor force is the fastest growing category -- a category with one of the lowest participation rates.

The harsh reality of Ben Carson's unemployment math is that the next president is going to face an American economy where a greater share of the burden of production will be placed on a smaller percentage of the working population, the results of an ever-expanding service economy, and the challenges of an aging society.

These are the realities that the candidates need to debate, because no amount of switching measurements is going to keep these realities from dominating the next presidency.