I recently received a cartoon from a friend that showed a psychiatrist having a session with her patient. She says, "You worry too much ... It doesn't do any good." And the patient answers, "It does for me ... 95 percent of the things I worry about never happen!"

Several years ago, I saw a survey that said 40 percent of the things we worry about never happen, 30 percent are in the past and can't be helped, 12 percent concern the affairs of others that aren't our business, 10 percent are about sickness -- either real or imagined -- and 8 percent are worth worrying about. I would submit that even the 8 percent aren't really worth the energy of worry.

I wrote a column about the Second 10 Commandments in 2009 and guess what No. 1 was: "Thou shall not worry, for worry is the most unproductive of all human activities." You can't saw sawdust. A day of worry is more exhausting than a day of work. People get so busy worrying about yesterday or tomorrow, they forget about today. And today is what you have to work with.

Robert Leahy, author of "The Worry Cure," says people worry for a variety of reasons, but one big reason is that worriers are intolerant of uncertainty. Leahy says worriers believe that they are being responsible by worrying because they believe they are preparing to avoid something bad. They think that by worrying they are taking control of their lives. But in fact, the reverse is true. Too much worrying causes people to lose control, and only builds their anxiety.

Worriers believe that they need to know what the outcome will be -- or there could be some kind of catastrophe awaiting them. Leahy says that worriers almost always overestimate the negative outcome.

At the same time, they underestimate their ability to handle what does happen. He further reminds us that worriers often forget that their past worries have mostly turned out to be futile.

I can attest to that finding. Instead of worrying about bad outcomes, I have adopted a different strategy. When I am faced with a big business decision or challenge, I ask my team to think about two things: What are we trying to accomplish, and what is the worst thing that can happen? We plan for the best, but we also prepare for the worst. That way, we avoid most surprises by anticipating disappointment.

Perhaps we would be wise to take some advice from folks who have been around long enough to have mountains of problems to worry about -- and yet, their longevity is credited largely to the right attitude.

Researchers at the Institute for Aging Research at Albert Einstein College of Medicine questioned 243 people aged 100 and older. They found that centenarians tend to share certain personality traits, in addition to other factors, like genetics. In general, those traits included:

-- Outgoing

-- Positive-minded about other people

-- Full of laughter

-- Open with their emotions

-- Conscientious and disciplined

-- Unlikely to obsess about anxieties or guilt

The scientists did point out that these characteristics don't necessarily represent the reason for the long life spans. But they did notice that in many cases the personality traits they observed weren't necessarily lifelong tendencies, but behaviors their subjects learned as they grew older.

Focusing on the positives and not worrying about the negatives may have a favorable impact on overall life expectancy. So maybe it is never too late to adjust your thinking. And please, don't worry if that change doesn't happen overnight. Old habits die hard.

The true futility of worrying about things reminds me of the story about Herbie, who worries all the time. He worries so much he can't sleep. He paces in the bedroom all night. His wife wakes up and asks him what's on his mind.

"I can't pay the rent," he says.

She says, "We'll talk about it tomorrow. Go back to sleep."

He tries to go back to sleep, but he just keeps tossing and turning and soon he's up pacing again.

Suddenly his wife picks up the phone and dials the landlord. "Hello," she says. "Herbie can't pay the rent this month." And she hangs up.

Herbie says, "What did you do that for?"

"Let them worry all night about the rent," she says.

Today is the tomorrow we worried about yesterday.

Mackay's Moral: Worrying casts a dark shadow that blocks any glimmer of hope.

Have you ever had one of those days when all you could think was, "Gosh, do I need a vacation."

Of course you have -- because all work and no play isn't good for anyone. A vacation doesn't have to be two weeks on a tropical island, or even a long weekend at the beach. A vacation just means taking a break from your everyday activities. A change of pace. It doesn't matter where.

Everyone needs a vacation to rejuvenate mentally and physically. But did you also know that you can help boost our economy by taking some days off? Call it your personal stimulus package.

An analysis by Oxford Economics for the U.S. Travel Association found that more than 40 percent of U.S. workers don't take their full allotment of paid time off (PTO) during the year, representing an average of 3.2 unused vacation days per worker in 2013 -- a total of 429 million workdays!

Aside from the risk of exhaustion and career burnout, unused vacation days have a negative impact on the U.S. economy as a whole. The study estimated that if employees took full advantage of their PTO days, the economy would enjoy the benefits of more than $160 billion in sales and $21 billion in tax revenues, as well as supporting 21 million jobs in areas like retail, transportation and manufacturing. Workers taking just a single additional day off would boost spending by $73 billion.

So go ahead and take some vacation. It's your patriotic duty.

And please, don't try the old excuse that you can't take time off because your esteemed presence is required at all times. No one is indispensable. No one. The place may not function as smoothly without you, but chances are the doors won't close, and you won't lose all your customers.

My friend, the late Zig Ziglar, had an interesting take on productivity and vacations: "Isn't it amazing how much stuff we get done the day before vacation?" So let that be your motivation: getting lots of work done in anticipation of being out of the office.

Summer is traditionally a great time for a vacation. Have you planned some time off yet?

You can detach from the workplace without worry and enjoy the break you deserve if you follow these simple steps before you leave:

-- Notify co-workers and clients. Let bosses, customers and colleagues know you'll be on vacation at least a week -- if not sooner -- before you take off. Let people know how long you'll be out of the office, when you'll be returning and who they should contact in the meantime. Set an auto-reply on your email, and leave the same information on your voice mail.

-- Prepare your co-workers. Talk to the people who will handle questions or problems while you're away. Help them troubleshoot by providing pertinent information like the status of current projects, names of possible callers and reasons they might call.

-- Straighten up. There's nothing as unmotivating as coming back from a great vacation to a workspace in complete disarray. Make the transition easier by cleaning up before you leave.

-- Get your mind in gear. If you are not accustomed to taking time off, you may have forgotten how to disconnect. It typically takes two to three days to get into vacation mode. A friend usually downloads a photo of his destination for his screensaver a couple weeks before vacation. It reminds him to enjoy the rewards for his hard work.

-- Turn off your electronics and explain that you will be available for no more than 15 minutes a day unless the place is on fire. Our smartphone world has created an army of work zombies. The temptation to work is too great when you can just tap your phone. Don't let technology ruin your break ... or your life.

-- Trust the people you work with to carry on. You might be pleasantly surprised at what gets accomplished in your absence.

And if getting away from the office is absolutely impossible, try what the Business School of Happiness calls "The One Minute Vacation." When time and money prevent taking a physical vacation, "The same relaxing benefits of taking a vacation can be found in minutes of simple meditation interspersed throughout the day. In fact, three one-minute sessions of deep breathing taken at pre-set intervals throughout the day may indeed deliver the deep sense of peacefulness that might have seemed elusive."

Mackay's Moral: Vacations aren't luxuries, they're necessities.

Once the famous Chicago merchant Marshall Field was walking through his Chicago store and heard one of his clerks arguing with a customer.

"What are you doing?" he asked the clerk.

"I'm settling a customer complaint," said the clerk.

"No, you're not," said Field. "Give the customer what she wants."

Is the customer always right? If you are a business owner, the answer almost always is yes. Otherwise, they aren't customers. They are people who do business with someone else.

Years ago, I saw a study for Travelers Insurance that showed persuading people to complain could be, in fact, the best business move a company could make. Only 9 percent of the noncomplainers with a gripe involving $100 or more would buy from the company again. On the other hand, when people did complain and their problems were resolved quickly, an impressive 82 percent would buy again.

I have a philosophy about customers -- ours or anyone else's. A customer who has a good experience with a company will tell five other people. But a customer who has a bad experience will tell 15 other people, and with social media today, it can become tens of thousands. So anything I can do to decrease the bad while increasing the good is right at the top of my agenda.

Part of that philosophy assumes that you will get a second chance. If you get that chance, don't mess it up. You may be looking at the best customer you've ever imagined.

Customers can also be your best teachers. True, you often learn a lesson the hard way. But it's an education in Customer Service 101 that you won't learn in any school.

Stew Leonard, founder of a famous chain of supermarkets in Connecticut and New York, said: "Customers who complain are your friends because they are giving you a chance to improve instead of just walking away."

No one likes to hear that they have done a lousy job, but criticism from customers is more valuable than praise. You want your customers to tell you when you screwed up, so that you can take care of the problem and take steps to ensure that it doesn't happen again -- to them or anyone else. If they don't tell you, they will walk away and they'll never come back. Worse, you are likely to alienate someone else in the future by doing exactly the same thing.

To paraphrase a famous line, ask not what your customer can do for you, ask what you can do for your customer.

Now put the shoe on the other foot. Think like a customer. Stop to consider whether your own customers are receiving fair treatment. When you have a complaint, you want it addressed quickly and fairly. When you approach the problem from the customer's side, the view is quite different.

As consumers ourselves, we should be able to expect a satisfactory result. When you don't get what you paid for, agree to, contract for, or reasonably should expect, you should look for a resolution to the problem. And you should give the vendor the opportunity to fix it. Isn't that what you would want your customers to do? Remember, most reputable companies want to make the customer happy.

I recommend following these steps:

-- Determine the solution you want. Do you want a replacement, your money back or some other remedy? Be specific so you can convey from the start that you expect a resolution to the problem.

-- Start in the right place. Don't go to the CEO of the company until you've exhausted the lower rungs. Customer service is usually the best place to start. If customer service can't help you, ask to speak with a manager.

-- Target where to take your complaint next. Don't just call headquarters and voice your complaint to the receptionist. Find out who has the authority to address your complaint.

-- Control your emotions. When you're overwhelmed with frustration, vent your anger in a letter -- but wait a few days to decide whether to send or rewrite it. Humorous complaint letters are more likely to get noticed and acted upon. Also, remember to single out those employees who tried to help. Praise can be just as effective as criticism.

-- Keep copies of all correspondence. A good record of your attempts to resolve the problem can be helpful if you ultimately need to take legal action.

Mackay's Moral: If a business knows what's good for it, it knows what's good for a customer.