What is, and should I use Weighted Average?

[ArcticWolf]

Hi,

I calculate Sickness and Absence (S&A) data for my company, by department.
Each department can have between 5 - 100 people in it. I currently do a S&A
% of the department and then as company as a whole.

Because in one team we could have 5/10 people off = 50% S&A rate, yet in
another department 5/100 = 5%.

Is there a better way of calculating the % S&A for each department that will
give more meaningful data?

Thanks in advance,

AW

 

[Bob Phillips]

Haven't you answered the question yourself, calculate the average per
department based on the number in that department.

Other than that, you have given us nothing to go on.

 

[Gary''s Student]

Good question!!

Never average the percentages.
Always get the totals and then calculate a percentage:

(5+5)/(10+100)=
10/110=
9.09%

 

[Glenn]

Hi,

I calculate Sickness and Absence (S&A) data for my company, by department.
Each department can have between 5 - 100 people in it. I currently do a S&A
% of the department and then as company as a whole.

Because in one team we could have 5/10 people off = 50% S&A rate, yet in
another department 5/100 = 5%.

Is there a better way of calculating the % S&A for each department that will
give more meaningful data?

Thanks in advance,

AW

You would use a weighted average for the company as a whole. With your example
above, the company would have a S&A rate of 9.09%, which is calculated as total
"off" / total people [(5 + 5) / (10 + 100)]. That would be different than if
you would "average the averages" [(50% + 5%) / 2 = 27.5%].

 

[smartin]

Hi,

I calculate Sickness and Absence (S&A) data for my company, by department.
Each department can have between 5 - 100 people in it. I currently do a S&A
% of the department and then as company as a whole.

Because in one team we could have 5/10 people off = 50% S&A rate, yet in
another department 5/100 = 5%.

Is there a better way of calculating the % S&A for each department that will
give more meaningful data?

Thanks in advance,

AW

If you are trying to get to a company average others have steered you
well. But you are asking about meaningful data for departments, and I
think you are already there.

If it is normal to have an S&A rate of 9% company wide, a department
with a rate of 50% is clearly above normal, even within a reasonable
margin of error, and despite that department having a staff of 10.