# Thread: Population and vaccination coverage

1. ## Population and vaccination coverage

HI,
I am new to this forum, so I am not sure I am in the right place to start a thread. please advice if this is not the case.
I need to determine the number of people vaccinated per year based on the population number by age group and the coverage rate.

I use a spreadsheet to try to determine the equation (enclosed), but I failed to go beyond 4 years and I cannot find the pattern to go beyond.
If I use the following naming convention:
PopY1(1 to8) the number of children aged 1 to 8 years and C1 the percentage coverage year1
I get the following
Year1 number vaccinated=Pop1(1to8) x C1
Year2 number vaccinated=Pop2(1to8) x C2 - Pop1(1to7) x C1 x C2
Year3 number vaccinated =Pop3(1to8) x C3 - Pop2(1to7) x C2 x C3 - Pop3(1to6) x (C1 -C1*C2)x C3
Year4 number vaccinated= Pop4(1to8) x C4 - Pop3(1to7) x C3 x C4 - Pop2(1to6) x (C2 -C2*C3)x C4 - Pop1(1to5) x (C1*C2*C3-C1*C3-C1*C2+C1) x C4

I would need to find what the equation is for each year for 10 years?
And then I would need to extrapolate for any age groups (1 to 5, 10 to 56,etc)
Do you think you could help or point me in the right direction.