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Assumption that 1/4 is population between 0 and 18 (based on a research report I read) = 75 Mn
Assuming these are equally spread across ages 0 to 18, 0 to 6 has 25 Mn kids, or roughtly 4 Mn kids / age ( 1 year band applicable for KG)
For every 25 kids there are 2 teachers typically and to account for all other suporting teachers, adding 1 so 3 teachers for every 25 kids ==> 12 teachers for every 100 Kids. = 4,000,000/100 * 12 = 480,000 = .48 Mn teachers.
As there are typically two sessions - morning and evening in a KG day of only 3 hours, half the number of teachers is sufficient. = .24 Mn teachers.
People generally live upto 75 years.
If we take equal distribution of all ages we get 4 million people in each age (1 to 75)
kindergarten is for kids with age less than 6 and more than 2 years hence total 4*4 million = 16 million
Each of the kindergarten may be operating in 2 shifts (morning and afternoon)
we will assume equal distribution of kindergarteners in morning and evening shifts
hence 8 million each.
each batch may be around 20 kids (as kids need more attention)
hence 8 million / 20 = .4 million
hence .4 million teachers.
Assumption:
I’m going to take into account only kindergarten teachers that haven’t retired.
A teacher works only a single shift a day.
The equation:
# of kindergarten teachers in the USA = [1+% Unemployed kindergarten teachers in the US] X [# of USA kids in the ages for kindergarten that goes to kindergarten] / [average # of kindergarten kids a kindergarten teacher handles a day]
Calculation:
[# of USA kids in the ages for kindergarten that goes to kindergarten]
Assumptions:
Sub equation = [# of USA kids in the ages for kindergarten that goes to kindergarten] = [# of kids in the age of kindergarten go to kindergarten] X [% of kids in the age of kindergarten go to kindergarten]
US populations = 330M.
95% of kids in the age of kindergarten go to kindergarten.
Average lifespan 80 years.
Age of kindergarten = 2-6.5 years old (4.5 years)
If the age distribution was uniform, the number of children was = 4.5/80 X 330M=18.7M. However, I assume that the distribution isn’t uniform, and there are more young children in the US than older people, so I’ll round it up to 20M kindergarten kids in the US.
[# of USA kids in the ages for kindergarten that goes to kindergarten] = 20M X 95% = 19M
[average # of kindergarten kids a kindergarten teacher handles a day]
Assumptions:
Sub equation= [average # of kindergarten kids a kindergarten teacher handles a day] = [average ratio of kids per teacher] X [actual capacity %]
Not all kindergartens are fully occupied; I assume they are 90% full.
The average ratio of kids per teacher is 1:20.
[average # of kindergarten kids a kindergarten teacher handles a day] = 20 X 0.9 = 18 kids a day.
[1+% Unemployed kindergarten teachers in the US]
Assumptions:
The distribution of kindergarten teachers in the US is not fully efficient, so there might be unemployment of teachers from time to time.
In addition, sometimes teachers can be sick or take days off.
Therefore, I assume that an additional 10% of teachers are not working.
Final Calculation:
# of kindergarten teachers in the USA = 1.1% X 19M / 18 = 1.16M.
There are helper teachers for K teachers. I will not be including those helper teachers.
My calculations include active teachers and not retired teachers.
Calculations:
Total K teachers in USA = Total K students / No. of students served by 1 teacher
Looking at some of the schools in CA, there are approximately 15 kids per kindergarten teacher.
Total K students:
Avg life of a person is 80 years. 300 M US population. So approximately 3.8 M people for each age.
K teachers = 3.8M / 15
= .253M teachers ~ 250K teachers
Total US Population=320 Million
Assume 10% being Kindergarten age.
Total # of kids= 32 Million
Assume 50% go to school and rest don't.
Total # of Kids gong to Kindergarten=16 Million
Assume Teacher to student ration =1/8
16 Million * 1/8= 2 Million Teachers.
kindergarten teachers in US = 1. # kindergarteners in US divded by 2. # of kids in a class
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