Back to overview

Estimate the demand for plastic bags in the US.

Hello! I was wondering how you would tackle this question. I considered only businesses that use plastic bags, but I do not think that is inclusive enough.

3
2.9k
18
Be the first to answer!
Nobody has responded to this question yet.
Top answer
Profile picture of Deleted
Deleted
Coach
edited on Mar 20, 2020
McKinsey / ex-Interviewer at McKinsey / I will coach you to rock those interviews

Hi!

I would go from the consumer perspective:

  • Approximately 300 Mio people in the US
  • Out of them: 75% who go to the stores (total population divided into 4 age groups: 0-20; 20-40; 40-60; 60-80 -> those who are 20 to 80 go to the stores) = 225 Mio
  • I would divide those 225 Mio into urban (80% = 180 Mio) and rural (20% = 45 Mio) because they have a different frequency of going to the stores and different demand for plastic bags
  • We could assume urbanites go to the stores at least several times a week (buying small quantities of food), let’s say 3 times using on average 1 plastic bag per visit = so, 180 Mio * 3 = 540 Mio plastic bags a week for urban population. Multiply it by ~50 weeks in a year and you get = 27 bn plastic bags a year for urban population
  • Rural population visits to the store are probably less frequent, like 1 every two weeks, so we could calculate with 0,5 times a week but they probably use more plastic bags, let’s assume 5. So, 45 Mio * 0,5 times * 5 bags = ~ 112 Mio plastic bags a week. Multiply this by 50 weeks and you get = 5,6 bn plastic bags a year for rural population
  • Overall yearly demand for plastic bags in the US = ~ 33 bn per year, or around 110 plastic bags per capita per year – which sounds realistic.

Hope this helps! If you want to brainstorm more on this feel free to reach out!

Best,
Daniel

Profile picture of Clara
Clara
Coach
on Mar 14, 2020
McKinsey | Awarded professor at Master in Management @ IE | MBA at MIT |+180 students coached | Integrated FIT Guide aut

Hello!

I would first of all clarify demand from which segments (e.g., consumers, companies, etc.) 

If, for instance, was for consumers, you can try to extrapolate the # of bags you use weekly: 

  • For groceries
  • In stores
  • For storage purposes
  • etc. 

Once you have the number, you can extrapolate to different age groups (e.g., babies and childen won´t barely use any, very elderly people will use less, etc.) 

Cheers, 

Clara

Anonymous
on Mar 16, 2020
Sounds good, I will practice with this method again. Thank you!
Profile picture of Deleted
Deleted
Coach
on Jun 29, 2020
FREE 1st session in November | From Lawyer to MBB | Top in FIT | 10x your structuring skills | Message to get Free Prep Checklist

Hi,

I would suggest that you should present your own approach and I would be happy to review. 

Meanwhile please see below my approach to segmentation in market sizing as well as examples of solved cases:

B2C:
-Demographics (Age, education, income, family size, race, gender, occupation, nationality)
-Behavioral (Purchasing behavior, customer journey stage, occasion & timing,
customer loyalty & interest, risk tolerance, user status) 
-Psychographic (Lifestyle, personality traits, values, opinions, interests of consumers) 
-Geographic (Geographical boundaries)

B2B:
-Company characteristics (Industry, company size, number of employees)
-Geography (Geographical boundaries)
-Purchasing Approach (Occasion & timing, customer capabilities, nature of existing relationship) 
-Personal Characteristics (Loyalty, risk attitude, user status)

B2G:
-Demographics  (Type of agency, size of budget, the amount of autonomy) 
-Geographic (Geographical boundaries) 
-Government Tier (Federal , State, Local, Quasi-governmental, International)
-Bid type (Closed, Open)

But sometimes you don’t need to segmentation. Here is an example of case that could be solved with high level top down approach - estimate the size of credit card market in the US:
https://www.preplounge.com/en/consulting-forum/how-should-i-approach-the-following-question-estimate-the-market-size-of-credit-cards-in-the-us-6695