Last night, I took my kids out for an American children’s holiday known as Halloween.
Kids (and some ahem… adults) dress up in costume (I was a penguin this year), go door-to-door, saying “Trick or Treat” and get free candy from the neighbors.
My three kids brought back a record 420 pieces of candy. 
In today’s New York Times, I learned that in the weeks leading up to this holiday, Americans purchased $2.7 BILLION dollars in candy.
So here’s my challenge for you.
Assuming all of that candy is consumed by someone in America, estimate the total number of calories represented by $2.7 billion in candy.
Assuming 3,500 calories consumed results in a person gaining 1 lb (0.45 kg) in weight, estimate how many pounds (or kilograms) of weight the American population will gain. Add a comment below to post your entry.
The winner will receive public acknowledgement of their estimation skills, and I will send them a portion of the candy “tax” I collected from my kids.
Yes, we tax our kids for a portion of their candy collection, as mom and dad provide “infrastructure” and “chaperone” services.
It’s a useful lesson in taxation.
(We tax at a 33% tax rate.)
Mostly it is an excuse to reduce the amount of sugar they will otherwise end up consuming.
For my kids, it’s an excuse to get rid of the candy they don’t like anyways.
Good luck and Happy Halloween!
Entries will be accepted for next 72 hours, and only entries posted as comments below will be considered. A winner will be announced next week.
UPDATE as of Friday, November 4TH AT 12PM ET: New entries are welcome, but not eligible to win, as contest has closed.
329 thoughts on “A Sweet Estimation Question”
In order to break it down, we will have to make the following assumptions:
1. 40% of Halloween candy is typically cheap sugar infused treats that can be bought relatively cheap at almost 5 cents per piece. This includes lollipops, toffees, and plain old hard candy. These typically are the lowest in calorie intake, and average at about 25 calories/piece.
2. 30% of the candy can be classified as medium level treats, such as twizzlers, gobstoppers, jawbreakers etc. These are at a slightly higher price point and can go up to 10cents per piece. I would also average the caloric intake of these treats as 40 calories/piece.
3. The final 30% of the candy would be labelled the “premium” candy, which are the M&Ms, butter crunch, snickers, reese’s etc. These are definitely higher in caloric intake as well as price. The average calories would be more around 70 calories per piece, while coming in at a 20 cent per piece price point.
Assuming all the candy is consumed, we are looking at the following breakdown of 2.7 billion dollars:
Calories consumed = (0.4*2.7Billion/0.05)*25 (0.3*2.7Billion/0.1)*40 (o.3*2.7billion/0.2)*70 = 540Billion 324Billion 283.5 Billion = 1,147.5 Trillion calories
Calorie to Weight Conversion: 327,857,142 Lbs
This works out to roughly 1lb per person. However, to really measure weight gain, we must now make another assumption. We must assume that a portion of these calories were burned as energy and the remaining portion stored as fat. If we are to assume that people intake 40% more calories during Halloween than their necessary requirements then only 40% of those calories can be considered when calculating weight gain as the remainder will be burned s energy.
So in conclusion, the amount of weight gain would be close to:
131,143,000 lbs.
Fin.
27,771,430 kgs weight will be gained in total.
Hi Mr. Cheng,
My estimate is that each person between 5-40 years will gain about 4 lb. The assumption is based on looking at the price per calorie of some of the most popular candies, such as Nestle, Kitkat, Snickers and Reese’s peanut butter cups, among different vendors. This gives us an average of 400 kcal per dollar (600 for Walmart, 300 for Target and Amazon).
With this information we can compute the calories that the american population bought for Halloween, giving us 1000 billion calories. Finally, to get the weight gained by the american population we need to estimate who would be eating these sweets. If these sweets were consumed uniformly by everyone, each person would put on 1 additional lb, while if only kids ranging from 5-15 years of age ate them, they would gain 13 lb. My solution is a compromise between these two numbers, assuming that people aged between 5-40 years will eat the sweets.
Thank you for the fun problem!
Hey Victor,
I am a senior industrial engineering student from Boğaziçi University, Turkey and I would like to share my estimation with you.
My estimation is ~173 million pounds.
Here’s my logic:
(Total Weight Gained)= (Number of Candies Sold)*(Average Weight Gain from one Candy)
Let’s break this down one level further:
(Total Weight Gained)= (Total $ Amount Spent/Average Price of a Candy)* (Average Amount of Calories a Pack of Candy Contains/Necessary Calorie Consumption to Gain 1 lb)
We are given;
Total Amount Spent: $2.7B
Necessary Calorie Consumption to Gain 1 lb: 3500 cal
In order to find “Average Price of a Candy” and “Average Amount of Calories a Candy Contains”, assuming Walmart can represent U.S. retail candy sales, I took Walmart’s online store as a proxy. Since it’s not possible to know the exact number of products they sold and the share of each particular product, I narrowed down my focus once more.
There is a list called “Best-Selling Chocolate” under Candy&Gum category. I noted down information from the Top 20 products. I collected price, weight, serving size and calories per serving information. Then my logic is as follows:
Average Price of a Candy:= Average of prices of Top 20 products
Average Amount of Calories a Pack of Candy Contains= Average Weight*( Calories per serving/ Serving size)
Average Price=~$11.2
Average Amount of Calories a Pack of Candy Contains= ~571g*(186cal/42.3g)=~2510cal
Coming back to my original equation, plug these figures in:
(Total Weight Gained)=($2.7B/$11.2)*(2510cal/3500 cal)=~173 million pounds
That number seems high, but if we divide it by the U.S. population of 320 million, on average, an American citizen gains around 0.54 pounds, approximately 250 grams. That seems reasonable.
Couple of issues:
1) Walmart may not represent U.S. retail candy sales. I am not really familiar with U.S. retail industry, but if Walmart is rather a discounter, then the average price of a candy may even be higher.
2) Top 20 products at Walmart may not represent total sales. Again, not familiar with U.S. candy consumption characteristics, if people are buying from candy shops rather than retail stores, those candy shops may have different prices and calorie content than those at retail stores.
3) We assumed that all calorie consumption realizes as weight gain. But due to Halloween, people may be also moving more than regular times; like decorating houses, walking from door to door, cleaning all around after kids fell asleep. Therefore net weight gain may be less than a pound from 3500 calories. It may mean we have overestimated.
I have my case interviews and midterm exams at the door, so I feel like I shouldn’t have been doing this. But overall, I think it was good practice for me. I hope, I’m close to your estimation!
Thanks Victor,
Çınar
Assume there are 320 Million people here in the United States
Assume that there are even number of people within each age group
Assume that everyone consumes on average the same amount of candy
Now we assume that each candy on average cost $.20, then $2.7 Billion dollars of candies will turn into 13.5 Billion of candies. Assume that each candy carries roughly 10 calories, that is a total of 135 Billion Calories.
Having all of this information, we now divide the total calories consumed by the American from candies (135B) by 3,500 Calories in order to estimate the total amount American will gain per kilogram through this holiday. With that division we will get 38.57 million or 40 million kilograms in total.
From a per person aspect, 40 million kilograms divided by the total U.S. population is 0.125. We can then conclude on our preliminary research that an average American gain about 0.125 Kg on Halloween!
Let me know what you think
A chocolate bar usually has around 200 calories per 50g and can be between 0.69 cents to 1.29 or so. For simplification we’ll just say it’s around 1 dollar.
Hard candy usually follows the same nutritional profile i.e. 200 calories per 50g but is usually cheaper. Based on the image above, it appears at least half of the candy is of the chocolate variety whereas the other falls into the hard candy category.
As a ballpark estimate, let’s say the lower price/calories ratio for hard candy gets us to being able to purchase 300 calories of candy on average for 1 USD.
Then our estimates are as follows:
1)Total amount of calories that will be consumed by the American public = 2 700 000 000 * 300 = 81 000 000 000 calories
2) Total amount of calories consumed per US citizen = 81 000 000 000/318 900 000(US pop) = 2539.98 calories
3) Total amount of weight that each US citizen is likely to gain as a result of Halloween on average = 2539.98/3500 = 0.73 lbs
Hi Victor, thanks for the Sweet Estimation Question.
My estimation is that the American population will gain around 49 million lbs in total.
I calculated this by:
1. Estimating that the average price of a Halloween candy would be around $1.25.
2. Dividing $2.7 billion by $1.25 to find how many candies have been purchased (2.16 billion candies).
3. Estimating that the average calories of a Halloween candy would be around 80 calories.
4. Multiplying the estimated number of calories for each candy to the estimated number of candies purchased (80*2.16 billion = 172.8 billion calories)
5. Dividing estimated total number of calories by 3500 calories (172.8 billion/3500 = 49.3714285714 million lbs)
372M pounds
Assuming 4 pieces of candy cost 1 dollar, 1 piece of candy has 100 kcal.
American Population will gain = total sells *pieces per dollar*kcal per pieces/3,500kcal per pound
=2.7B*4*100/3,500 = about 308.6M lbs
Fun question, Victor!
Let’s jump right in.
It’s a been a few years since my trick-or-treating days came to an end, but I recall there being two distinctly different types of houses. There were the stingy (read: responsible) folks that handed out the mini “”fun sized”” packages, and there were those that doled out sweets the way they were meant to be enjoyed, full-size, like you’d see in the checkout aisle of your local grocery store. Looking back, my hypothesis is that the cost-to-calorie ratio that these two household “”segments”” bought candy at would surely be different. Let’s take a closer look.
First, the “”stingy”” household segment:
– Nestle Assorted Mini Candy Bars (50 ct.): $8.97 for 2,525 cals
– Maynards Assorted Candy Treats (70 ct.): $11.97 for 3,115 cals
– Cadbury Mini Bars (100 ct.): $13.97 for 4,500 cals
– Hershey’s Assorted Candy Bars (50 ct.): $9.48 for 1,923 cals
– Mars Assorted Fun Size (50): $7.97 for 3,189 cals
I’m on my lunch break so I’m not going to research the market shares of these companies (which would allow us to weight these different costs for a more accurate estimate), but this gives us a cost of $3.59 per thousand calories.
But let’s not forget those amazing folks who handed out the full-sized candy bars! We’ll call them the “”generous”” household segment. I repeated the same very boring analysis on both the 4-packs and single portions of regular-sized Mars, Twix, Oh Henry!, and Skittles, then averaged them. We end up with a different cost at this larger portion size: $3.18 per thousand calories.
Who would’ve guessed! Buying your Halloween candy in bulk doesn’t actually save you money on a per-calorie basis! Turns out the folks giving out full candy bars aren’t just generous, they’re penny-wise too!
Now I’m not sure about your neighborhood, but in mine, the “”stingy”” households were definitely in the majority. Let’s assume 75% of houses were giving out small packages, and the remaining 25% were delighting parents with jumbo-sized sugar highs.
75% * $3.59 25% * $3.18 gives us our weighted average cost per thousand calories: $3.49
This allows us to translate our figure of $2.7 billion worth of candy into just shy of 775 BILLION calories – candy that’s metaphorically going straight to the thighs of today’s youth (and those of their parents… *cough* Victor *cough*)
Or, more precisely, they’re going there at a rate of 3,500 calories per extra pound of flab…
Congratulations America! This Halloween, you’ve gained a collective 221 million pounds. That’s almost a full pound (0.95) for everyone under the age of 55. The optimist in me thinks maybe it’s a little less than that if the “”taxes”” imposed by parents like Victor are going into the garbage can and not down their gullets.
Still, that’s scarier than any group of clowns will ever be…