Percentages

[Don]

I have a spreadsheet that I use to track manpower usage. I have been asked to
reduce hours or days worked by 3% on average per month and not to exceed or
fall short of the goal (within reason). I must also be able to track the
reduction for reporting purposes. Since I have to reduce by 3% for the entire
month and not per day it gives me flexability to work people at various
shifts or hours ie 3, 8 hour shifts instead of 2.4 hours per day over 10
days. I have an entry sheet for each day of the month that I enter the hours
of reduction that links to the next day's sheet (31 sheets in all). To use
the flexability, some days I may be able to achieve a 10% reduction while
other days it may be 0%. I need to somehow add all of the daily percentages
or affected hours from sheet to sheet and arrive at a realtime monthly
average that displays on the top of every sheet letting me know when I have
achieved 3% and when I fall short and I have to plan to defer work to meet
the 3% goal. My problem (among many others) is do I start with all of the
possible hours in a month and have the calculation for each day adding from
page to page the hours saved totaling those hours on the last page to show a
running total to claculate the percentage? I know I can link the value to
display on each sheet. And if I do this will it be accurate or do I have to
divide the result by say 30 days or variation of days? I have tried to add
all of the saved or redirected hours from day to day and divided by to total
available month to date hours but I seem to be doubling the percentage each
day. I then thought I have to divide that percentage by the amount of days
tracked but it does not seem acurate either. Please advise.

 

[Joe User]

I need to somehow add all of the daily percentages
or affected hours

You should work with the daily hours, not the daily percentages.

In order to achieve a 3% reduction for the month, you need to achieve a 3%
reduction each day __on_average__.

You can monitor that by maintaining a cumulative sum of the current daily
hours and comparing that against the cumulative sum of previous daily hours
for the same period.


----- original message -----

 

[Dennis Tucker]

I think you are making this way too complicated than it needs to be.

First thing, determine what is the average number of work hours per month.

Take this value and multiply it by .03(3%). The value you get back is the
number of work hours that you must trim(reduce).

Then it is up to you and your scheduling of labor to ensure that those hour
are reduced that much.

You may what to figure out what is the average number of work hours per
week. If you wanted to reduce by 10 hours in this week but it worked out to
be higher or lower than expected, then you know that you need to make either
a larger or smaller correction in the next week.