Rule of 72

When I started investing money in assets like fixed deposits, recurring deposits and public provident fund (PPF) I usually ask myself, when my investment would double/triple/quadruple etc.

I pick my pencil and do calculations on paper using formulas of compound interest and I   overwhelmed by large calculations. I even used calculators, but computing that period in which your money would double/triple/quadruple with a given rate of interest on a calculator may require significant time and efforts.

I asked the same question with my friends, if I fixed deposit 10,000/- for 8% per annum, In how much time will my amount would be doubled/tripled or quadruple and so on ?. But I realised lot of people do not even know the formula of compound interest and simple interest. And those who knew it, also not able to do it easily. Compound Interest is more complex to calculate, and it requires a pre-requisite knowledge of how compounding formulas work.

Later I found a shortcut called Rule of 72. Using  this shortcut, I was able to calculate that period in a blink of an eye, that too, mentally.  It is a great mental shortcut to estimate the effect of any growth rate, from quick financial calculations to population estimates.

(i) Rule of 72 i.e. Doubling Period(2X)

Divide 72 by the interest rate. The answer you get is your Doubling Period.

Years to double = 72 / Interest Rate

rule of 72


  • If the rate of return is 8%, you can expect your money to double in 9 years (Dividing 72 by 8=72/8=9)
  • If the rate of return is 12%, you can expect your money to double in 6 years (Dividing 72 by 12=72/12=6)
  • To double your money in 10 years, get an interest rate of 72/10 or 7.2%.
  • If your country’s GDP grows at 3% a year, the economy doubles in 72/3 or 24 years.
  • If your growth slips to 2%, it will double in 36 years. If growth increases to 4%, the economy doubles in 18 years. Given the speed at which technology develops, shaving years off your growth time could be very important.
  • If inflation rates go from 2% to 3%, your money will lose half its value in 24 years instead of 36.
  • If college fees increases at 5% per year (which is faster than inflation), fees costs will double in 72/5 or about 14.4 years.
  • If you pay 15% interest on your credit cards, the amount you owe will double in only 72/15 or 4.8 years!

Now understand, what is the shortcut to calculate the tripling/quadrupling period with a given rate of interest.

  • Tripling Period(3X)  [Rule of 114]
    Divide 114 by the interest rate. The answer you get is your Tripling Period.
    For example:
    Taking the 8% interest rate, you can expect your money to triple in approx. 14 years(Dividing 114 by 8=114/8= approx 14)


  • Quadrupling period(4X) [Rule of 144]
    Divide 144 by the interest rate. The answer you get is your Quadrupling Period.
    For example:
    Again let 8% is the interest rate, You can expect your money to quadruple in 18 years  (Dividing 144 by 8=144/8=18)

Aha ! This is so simple now. With some practice, you would be able to calculate the doubling/Tripling/Quadrupling period of your investment at a given rate of interest without even needing to pick up a calculator, or for that matter, a pen and paper.

There is a very implicit learning is hidden in the rule of 72.

Let’s us consider rate of interest is 8%.
The time period for your investment to double is , 9 years.

Now, notice the time period for your investment to triple is 14 years. In other words, the investment which became 2X in 9 years, took just 5 additional years to become 3X.

Notice, The time period for your investment to quadruple is 18 years. In other words, the investment which became 2X in 9 years, 3X in the next 5 years, reached 4X in just 4 additional years. Continuing further, it would take lesser time for the same investment to grow 5X, 6X and so on. This is the magic of compounding interest.

Thus, here’s is the very important financial lesson:

Always invest for the long term, to reap full benefit of compounding.


The above formulas do NOT give an “exact” doubling/tripling/quadrupling period. They are helpful for calculating the approximate period. Also, they may not be accurate for large rates of interest, like 30% or 40%, they work well for smaller rates of interest. To get more accurate and precise for large ROIs as well as for small ROIs divide by 69.3 (Rule of 69.3).

Never Wake Up to Tea or Coffee

  • Never start your day with caffeine – be it coffee or tea. Caffeine should not be the first thing that you give your body on an empty stomach.
  • EAT real food within 10 – 15 minutes of waking up. Pick up that glass of fresh juice or even better a bowl of fruits or simply sip some warm water to kick-start your system.
  • Wake up → Warm water → Breakfast → Coffee

For most of us, getting our morning coffee/tea is an absolute necessity. It has a special meaning in each of our lives.  Most of us are compulsive tea drinkers and cannot imagine our morning without bed tea.  Drinking bed tea, first thing in the morning, is a common practice in most Indian households and we all love to start our day with a piping hot cup.

Drinking coffee has tons of health benefits, such as protecting your brain from dementia, antioxidants in black tea or the catechins that can boost your immunity and your metabolism etc. Caffeine is known to give you an instant energy boost.

However, giving your body a strong dose of caffeine on an empty stomach may have side effects that include nausea, dizziness and other unpleasant sensations. It is also very bad for health and digestive system. In this article, I have we’ve rounded up five reasons why it is best to avoid tea as the first thing you have in the morning.

Drinking Tea on Empty Stomach Mask your hunger and keep you hungry for long time

When you sleep, your blood sugar level drops in the night. In the morning our liver stores are almost empty. So our blood sugar is low. That is why we feel ‘low’ and ‘lazy’ in the morning.

Our body breaks down our muscles and lean tissue into glucose to keep our sugar up.  Which is not anyway good for our health. So to keep our body’s fat burning tissue (muscle) alive we must eat real food.  Eating real food slowly increases our blood sugar levels. This kicks in action of insulin, which is secreted by the body as a response to an increase in blood sugar levels, which facilitates our hungry cells to get the nutrients that it is craving for.

But many people drink coffee/tea on empty stomach instead of eating real food. Stimulants provided through tea and coffee increase blood sugar level but provide zero nutrition to the cells that have been starving for the last 9 to 10 hours or more. Moreover the strong cup of coffee/tea can mask your hunger, so you go hungry without realizing a long time. All it does it create a huge calorie deficit in the morning and then the body has no other option but to overeat later to make up for the deficit.

Going hungry in the morning is a disaster for anybody who dreams of a great and fit body.

Caffeine is known to give you an instant energy boost. However, giving your body a strong dose of caffeine on an empty stomach may have side effects that include nausea, dizziness and other unpleasant sensations. It is best to have tea or coffee after eating something.

Dehydrates your body
Tea is diuretic in nature which means that it removes the water from our body. Our body is already dehydrated due to eight hours of sleep and intake of water or food, tea only adds to that state of dehydration. Excessive dehydration will eventually cause an imbalance in minerals leading to muscle cramps.”

Drinking Coffee empty stomach builds tolerance for the drug, which diminishes the effect

Our bodies produce a hormone called cortisol (“stress hormone”) when we are either stressed or fearful. Cortisol hormone is also a key component of our natural, day-long hormonal cycle, known as the circadian clock, which helps wake us up in the morning and wind us down at night.

The gist is that when our body releases cortisol, we feel more awake. Cortisol levels are highest in the morning. There are two basic problems with consuming caffeine when cortisol production is high.

First, caffeine tends to interfere with the production of cortisol. The body then produces less of the hormone and relies more on the caffeine.

Second, drinking coffee while cortisol is high leads us to develop long-term tolerances for caffeine, which is why so many habitual coffee drinkers say it has less of an effect on them. In effect, caffeine replaces the boost we would ordinarily get from cortisol rather than supplementing it. so that there are many coffee drinkers complain coffee is ineffective.

Hence coffee consumption has fostered a decrease in the amount of cortisol their body produces during the day.

So what is the ideal time to have coffee/tea ?

Between roughly 10 a.m. and noon, and 2 p.m. and 5 p.m. Between these hours, the coffee is actually most needed and you will get the most out of their caffeine., and, perhaps most importantly, will not interfere with our body’s own essential mechanism for keeping us alert.

Drinking Coffee at empty stomach Disrupts your metabolic activity

Drinking tea right in the morning may disrupt your metabolic system due to imbalance of acidic and alkaline substances in the stomach which can interfere with the regular metabolic activity of the body and keep you troubled through the day.

Drinking Coffee/tea at empty stomach Increases Acidity

Acidity in stomach and heartburn is very common nowadays. Coffee/Tea may cause acid reflux and heartburn. It may become more obviously while having a cup of coffee in the morning on empty stomach. When your stomach is empty, the acid doesn’t really have much to work with. Coffee will stimulate the secretion of gastric acid which may burden the stomach and cause abdominal distress.

It is found that quitting tea/coffee on empty stomach reduces acidity problem dramatically.

All that java will jumpstart the stomach’s production of acid, and if you haven’t already eaten something, the acid could damage your stomach’s lining and cause indigestion and heartburn. That goes for decaffeinated coffee, too.

Drinking Coffee/tea at empty stomach Increase Anxiety

Moderate drinking coffee at the right time may decrease your depression and makes you feel refreshed. However, contrary to this statement, When you consume a cup of coffee in the morning, your brain’s ability to process serotonin, a happy and calm hormone, may be weakened. In this way, you will feel anxiety and depressed. It can also boost your heart rate, irritability, and inability to focus.

Morning Tea can cause erosion of enamel in your teeth because of the presence of sugar

When you consume tea early morning, the bacteria in your mouth will breakdown the sugar which leads to increased acid levels in the mouth and this can cause erosion of the enamel in your teeth. It may even cause gingivitis due to excessive bacteria build up.

Milk in the tea may cause bloating 

Due to the presence of milk in the tea, many people may feel bloated majorly because of the high lactose content in the milk that can affect your gut when it is empty. This can lead to gas and constipation.
Caffeine on an empty stomach can wreak havoc with your digestive tract. 

Hydrochloric acid has a very important function to support the digestion of food and is therefore released when you eat, smell or even start thinking about food.

“Coffee, even decaffeinated coffee, has been shown to stimulate production of acid which, in the absence of food, can be damaging to the lining of the stomach with repeated exposure.

Start your morning with healthy substitutes

Do Remember this order: Wake up → Warm water → Breakfast → Coffee

Wake up with a cup of warm water or consume alkaline drinks in the morning like buttermilk, or lukewarm water with a pinch of Himalayan pink salt. You can even start your day with lime water or methi water to reboot your system after long hours of rest. A few drops of coconut vinegar or apple cider vinegar with water, plain coconut water, raw honey and aloe vera juice are also good options.

and then have your breakfast (must have). This is the time to eat and to eat big. Eat anything like fruits, paratha, poha, roti, sabzi, upma, dosa etc. Anything that is fibre rich. Your cells receive nutrition through food and blood sugar comes to an optimum level and your metabolic activity starts functioning properly.

Finally, serve yourself a cup of delicious coffee/tea.  So ideal time to have tea is mid-morning after having your breakfast. The breathing rate, heart rate etc will still increase but now your first meal or breakfast will act as buffer.

Follow this order and you will not suffer from the above side effects of drinking coffee on an empty stomach.

Wake Up Early

Early to bed, early to rise makes a man healthy, wealthy and wise”. – Ben Franklin, famously

Fresh Air, less noise and light atmosphere

When you wake up early in morning, you find a very light atmosphere filled with fresh air around you.  This is the only time, when noise pollution is very less. Your mind gets clarity for the day as you plan. Studies have suggested that when a person gets up early, he is more energetic and takes lesser time to do a task that would take more time otherwise.

You are more energetic and take lesser time to do a task that would take more time otherwise. He is also more adept in taking better decisions, planning and achieving goals.

Better Productivity

Some of the most successful people in the world are early risers. It’s simple, if you wake up early, you get more done.

You will get extra hours everyday to work for your dreams or important projects. Besides allowing you more hours for your work, it also boosts your speed.  Your productivity increase. You feel inspired and motivated as you complete your tasks before time. This will overall affects your entire life, your career and your finance. Studies have suggested that when a person gets up early, his income also increases dramatically.

If you’re studying, you should know that research conducted by Texas University found that students who consistently woke up early each day actually scored better test scores and overall grade points, and consistently kept a higher average GPA than their night owl counterparts.

There are less distractions in the early hours of the day so you can achieve more with minimal interruptions. Your brain is in relaxed mode after a good quality night sleep, so you can do difficult mental and creative work in this morning time with more efficiency. And the perk is that you can all these quicker and better.

Mental Fitness

The person who wakes up early, has strong mind compared to the one who wakes up late. He takes better decision. Your stress level also reduces dramatically.  You start your day on an optimistic note and such positivity often stays with you throughout the day. This is the time of the day when you are not in rush. You start your day with smile, relax mood and clarity.  He is also more adept in taking better decisions, planning and achieving goals.

Obviously a rested mind is more prepared for what the day has to throw at it. Because you will be more organized and energized, you are also more prepared to take on what life throws at you.

Studies have shown “morning people” are often more positive, more optimistic and more likely to experience satisfaction in their lives.

Better Sleep Quality

Early risers often go to bed early. Getting up early is not something that should be followed irregularly but it needs to be well established as a routine in your life. This means going to bed early, and most likely at the same time every day and waking up early at the same time everyday. This translates into better sleep quality as your body’s internal clock adapts to your new sleep routine. You are also keeping your body in a circadian rhythm. Think of this as an internal clock that cues your body to do certain things at certain times of the day. This rhythmic pattern also supports how your brain functions.

Waking Up Early Improves Your Quality of Sleep.

Remember,  If you are already waking up early but on weekends you wake up late, than this will harm you more to your body in long run. Always maintain a disciplined routine even on weekends or vacations.

Quite Time

There is a lot of power in “quiet time” and early risers often talk about enjoying the quiet time of earlier starts. By waking up early than the rest of the family, you probably have more quiet time to yourself at home. But this quiet time isn’t limited to home alone.

If you commute to work, early starts will see you avoiding the peak hour congestion and enjoying a quiet(er), more peaceful commute to work. Also, speaking from personal experience, I have found that I really enjoy starting work earlier than my other colleagues.

I relish the first couple of hours of my day as it’s distraction-free and it’s a great time to make important decisions as I am the most focused.

Even just sit and enjoy the silence of the morning in meditation. Or Pour your cup of coffee and watch the sun rise. This period of silence can actually be incredibly beneficial to your brain as well. Sitting in silence increases oxygen to your brain as your breathing generally becomes deeper and more controlled. This helps reduce migraines, high blood pressure, and overall taxation on your body to name a few.

Waking Up Early Helps You To Sustain a Healthier Diet

This is the most fav benefit I received from waking up early. I am following waking up early routine since a long time. My entire eating schedule is changed now. My metabolism is very strong. I eat better food and at proper time.

After I wake up I drink 1 glass warm water and then I eat some fruits. I do Yoga for one hour and then I eat powerful nutritious breakfast. If you wake up early, you never skip your breakfast and You will have your lunch and dinner on time. If your take your dinner early and on time, then you get proper time gap between your dinner time and sleep time. And you will have better sleep.

When you wake up late, chances that you skip your breakfast meal and your body goes into starvation mode so the next time you actually eat something, you are more likely to overeat and crave unhealthy foods.

Life Tip  – Never skip your breakfast.

Breakfast is most important meal of the day. Your body has been on a “fast” all night (6 to 8 hours) and you need to “break the fast” with some healthy food.  Eating breakfast is also a foundation for building healthy eating habits and makes you less likely to eat junk the rest of the day.

Waking Up Early Gives You More Time To Exercise

Studies proved that morning time is best time for exercise and yoga.  So if you’re trying to commit to a regular exercise routine – make morning time your exercise time. If you want to find a reason for waking up early, then this can be your best motivation. Exercise and waking up early are a great way to combat lethargy.

Starting your day with a workout doesn’t only cut your early evening fatigue out of the equation, it is also super healthy for you! It burns more calories, and continues to do so at a higher rate after you have finished, plus it helps you sleep better at night. Exercise releases endorphins too, which area feel good hormones: making you start your day out in a good mood as well.

More Energy throughout the day

Better rest equals more energy.  Early risers generally have better sleep patterns than night owls. Once you drop into deeper cycles of sleep, your blood pressure drops, breathing slows, muscles are relaxed, body temperatures drop, and the blood supply to your muscles increase. This results in tissue and bone both repair, as well as cellular corrections. Growth hormones are also released that are essential for muscle development.