# Excel formula **URL:** \ **Category:** Factual Questions\ **Created:** [February 12, 2010, 1:58pm UTC](https://boards.straightdope.com/t/excel-formula/528699 "2010-02-12T13:58:28Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![robcaro](https://avatars.discourse-cdn.com/v4/letter/r/df705f/32.png) [@robcaro](https://boards.straightdope.com/u/robcaro)\ **Post date:** [February 12, 2010, 1:58pm UTC](https://boards.straightdope.com/t/excel-formula/528699/1 "2010-02-12T13:58:28Z")
Using Excel 2000. I have a number in a cell that I want to be minus 3%. It is: 215,000,000-3% but I cannot get it to work. Can anyone here help me? I am using =sum(215000000-3%) ---
**Author:** ![dasgupta](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@dasgupta](https://boards.straightdope.com/u/dasgupta)\ **Post date:** [February 12, 2010, 2:01pm UTC](https://boards.straightdope.com/t/excel-formula/528699/2 "2010-02-12T14:01:21Z")
How about =CELL \* .97 (or 97% of the value)? Or if you want to keep the 3% as a reference, =CELL - (CELL \* .03). ---
**Author:** ![Munch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/munch/32/5281_2.png) [@Munch](https://boards.straightdope.com/u/Munch)\ **Post date:** [February 12, 2010, 2:34pm UTC](https://boards.straightdope.com/t/excel-formula/528699/3 "2010-02-12T14:34:03Z")
> [@robcaro](#): > > I am using =sum(215000000-3%) 1. Is the number an actual sum (i.e. =sum(A1:A23))? 2. Excel doesn’t use the “%” sign. Like dasgupta showed, you should just multiply it by .97: [number]_.97, or go with =[number]-[number]_.03 ---
**Author:** ![robcaro](https://avatars.discourse-cdn.com/v4/letter/r/df705f/32.png) [@robcaro](https://boards.straightdope.com/u/robcaro)\ **Post date:** [February 12, 2010, 3:57pm UTC](https://boards.straightdope.com/t/excel-formula/528699/4 "2010-02-12T15:57:36Z")
I did it with =SUM(E2-(E2\*0.03))… Thanks for your help. ---
**Author:** ![Ruminator](https://avatars.discourse-cdn.com/v4/letter/r/b9bd4f/32.png) [@Ruminator](https://boards.straightdope.com/u/Ruminator)\ **Post date:** [February 12, 2010, 4:13pm UTC](https://boards.straightdope.com/t/excel-formula/528699/5 "2010-02-12T16:13:21Z")
> [@Munch](#): > > 1. Excel doesn’t use the “%” sign. Actually, Excel can use “%” sign. I use it all the time in formulas to help readability. For robcaro’s example, instead of… ```auto =sum(215000000-3%) ``` …its… ```auto =215000000*(100%-3%) ``` ---
**Author:** ![Munch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/munch/32/5281_2.png) [@Munch](https://boards.straightdope.com/u/Munch)\ **Post date:** [February 12, 2010, 4:28pm UTC](https://boards.straightdope.com/t/excel-formula/528699/6 "2010-02-12T16:28:09Z")
> [@robcaro](#): > > I did it with =SUM(E2-(E2\*0.03))… Thanks for your help. Again, you don’t need the “SUM” in there, because you’re not adding anything. It’ll work just fine as =E2-(E2\*.03). Try it. You’ll get a lot more functionality out of Excel once you start understanding stuff like that. ---
**Author:** ![jjimm](https://avatars.discourse-cdn.com/v4/letter/j/ba8739/32.png) [@jjimm](https://boards.straightdope.com/u/jjimm)\ **Post date:** [February 12, 2010, 4:34pm UTC](https://boards.straightdope.com/t/excel-formula/528699/7 "2010-02-12T16:34:40Z")
> [@Munch](#): > > Again, you don’t need the “SUM” in there, because you’re not adding anything. It’ll work just fine as =E2-(E2\*.03). Try it. You’ll get a lot more functionality out of Excel once you start understanding stuff like that. Or more elegantly, =E2-(E2\*3%) ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [February 12, 2010, 5:15pm UTC](https://boards.straightdope.com/t/excel-formula/528699/8 "2010-02-12T17:15:26Z")
> [@jjimm](#): > > or more elegantly, =e2-(e2\*3%) =e2-(e2\*.03) ---
**Author:** ![robcaro](https://avatars.discourse-cdn.com/v4/letter/r/df705f/32.png) [@robcaro](https://boards.straightdope.com/u/robcaro)\ **Post date:** [February 13, 2010, 12:43am UTC](https://boards.straightdope.com/t/excel-formula/528699/9 "2010-02-13T00:43:29Z")
Thanks so much for all the good information. Still learning I guess. ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [February 13, 2010, 2:09am UTC](https://boards.straightdope.com/t/excel-formula/528699/10 "2010-02-13T02:09:06Z")
> [@robcaro](#): > > I did it with =SUM(E2-(E2\*0.03))… Thanks for your help. Eventually, you are going to want to use a different percentage. It’s always more convenient to put parameters in cells rather than hardcoding them into formulas. I suggest you put the value 3% in a cell (let’s say E3) and do this =E2\*(1-E3) ---
**Author:** ![jjimm](https://avatars.discourse-cdn.com/v4/letter/j/ba8739/32.png) [@jjimm](https://boards.straightdope.com/u/jjimm)\ **Post date:** [February 13, 2010, 9:22am UTC](https://boards.straightdope.com/t/excel-formula/528699/11 "2010-02-13T09:22:44Z")
> [@Magiver](#): > > =e2-(e2\*.03) 😕 See post directly above mine. ETA: **robcaro** , stop with the SUM - that’s generally only required for adding ranges of numbers and cells. It’s entirely unnecessary for simple functions like yours.