Calculating incremental difference between 2 percentages
- Thread starter Tal71
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lev888
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You want to insert 4 numbers so that they are all equally spaced? Ok, how many equal spaces will you have? And how big each space will be?
Hi Lev, thanks for your response.
I'm not sure how to explain it clearer than I did in my first post but I'll give it a go! There will be 4 evenly spaced percentages between the first and last percentages provided (Which are entered manually for Jan & Jun) - I need to work out what percentages will fill the gaps (assuming a steady increase between Jan & June). The percentages entered/calculated for each month is how much the starting figure for each month (entered manually) will be reduced by
Example:
I'm not sure how to explain it clearer than I did in my first post but I'll give it a go! There will be 4 evenly spaced percentages between the first and last percentages provided (Which are entered manually for Jan & Jun) - I need to work out what percentages will fill the gaps (assuming a steady increase between Jan & June). The percentages entered/calculated for each month is how much the starting figure for each month (entered manually) will be reduced by
Example:
| Jan | Feb | Mar | Apr | May | Jun | |
| Starting Figure | 27.0 | 31.6 | 28.2 | 23.1 | 18.9 | 5.1 |
| Reduced by | 20% | 70% | ||||
| Result | 21.6 | 31.6 | 28.2 | 23.1 | 18.9 | 1.5 |
Harry_the_cat
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Do you want the difference in the percentages to be the same
Ie 20, A, B, C, D ,E, 70 where A-20= B-A= C-B etc.
Or the ratio to be the same
Ie A/20=B/A=C/B etc ?
In other words, an arithmetic progression like 2, 4, 6, 8, 10 or a geometric progression like 2, 4, 8, 16, 32.
Ie 20, A, B, C, D ,E, 70 where A-20= B-A= C-B etc.
Or the ratio to be the same
Ie A/20=B/A=C/B etc ?
In other words, an arithmetic progression like 2, 4, 6, 8, 10 or a geometric progression like 2, 4, 8, 16, 32.
lev888
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Let's simplify. If you need to insert one number between 20 and 70, what would it be?
lev888
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Ok, how did you calculate it?
HallsofIvy
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Three equally spaced points, between a and b, will divide the interval into four equal spaces between them
Divide b- a by 4, (b- a)/4, so that each of the four spaces has length (b- a)/4. The three points are a+ (b- a)/4= (4a+ b- a)/4= (3a+ b)/4, a+ 2(b- a)/4= a+ (b- a)/2= (2a+ b- a)/2= (a+ b)/2, and a+ 3(b- a)/4= (4a+ 3b- 3a)/4= (a+ 3b)/4.
Divide b- a by 4, (b- a)/4, so that each of the four spaces has length (b- a)/4. The three points are a+ (b- a)/4= (4a+ b- a)/4= (3a+ b)/4, a+ 2(b- a)/4= a+ (b- a)/2= (2a+ b- a)/2= (a+ b)/2, and a+ 3(b- a)/4= (4a+ 3b- 3a)/4= (a+ 3b)/4.
Thank you! This gave me what I need
