percentages
percentages
(OP)
Say a project is estimated for a dollar and the actual price is two. What is the best way of expressing this fact using percentages rather that dollars? Please assume a non-technical audience. I like 200% because it looks higher, but I do not wish to falsely convey the project exceeded the estimate by 200%. For the sake of clarity, I opted to use both figure. "The final price was 200% of the estimate, or 100% over." Alas my attempt at clarity has failed, since my test readership (my wife and son) were 100% confused by my use of two figures. "Which one is it?"
What's your advice? Thanks.
What's your advice? Thanks.





RE: percentages
Like if gas price goes up from $1.00/gal to $1.50. Probably its better to say the price increases 50%.
RE: percentages
RE: percentages
RE: percentages
RE: percentages
If I say the price of gas goes up 50% (less than 100%), most people will understand it. But if the price goes up from $1.00 to $2.50 and you say the price goes up 150%, I bet cha a lot of people would think the price is $1.50. So I say put the actual number on the top of the %.
RE: percentages
I would say that if you want to be neutral, then just state the numbers.
"The estimate is $1. The actual price is $2."
If you want to highlight the fact that things are more expensive now, then use the highest number in whatever units that give the impression of a large increase.
"The actual price is 200% of the original estiamte. This increase is due to ..."
If you want to minimise the fact that things are more expensive, then use the smallest number in whatever units that give the impression of a small increase.
"The original estimate was 50% of the actual price. This increase was due to..."
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: percentages
If you are trying to communicate (with clarity) to a non-techincal audience, you should use language which they will understand;
"The final price (cost ?) was twelve and a half times the estimated price."
As was proved with your test audience, numbers (especially percentages) can be too easily mis-understood but, if you really want to bamboozle them, you could then back up the plain English with large percentage numbers ;
"That's 1,250% !!!"
RE: percentages
"The original estimates were 50% of the final cost."
Or
"The project was on budget." With a a foot note in 2-point type explaining that the budget was re-baselined the day before the contract was closed.
RE: percentages
Percentage has nothing on permillage.
RE: percentages
Percentages appear to have more meaning when it is less than 100%. If over 100% I think terms like "2-fold increase" or "threee times as much" convey more meaning with less chance of confusion.
RE: percentages
RE: percentages
RE: percentages
Final costs were double the estimate.
Per Cor blimey.
If you really want to flag how much that was then say
Giving a total overspend of $xxx.
% etc will cause confusion to some, I had a similar conversation with Designer here on a technical report someone else had given him. I would like to think most Engineers (and probably bean counters) would understand the difference but there are a lot of other personel around who may not.
RE: percentages
RE: percentages
However your interpretation of applying the "2-fold increase" (in your previous post) amazed me because if I applied that logic to the $1 example I would have $3 ... I don't understand how a "2-fold increase" can be interpreted to mean "3 times the estimate".
Two-fold = double.
http://dictionary.reference.com/browse/double
If someone ate a double portion of something, did he/she eat two or three portions?
RE: percentages
"If someone ate a double portion of something, did he/she eat two or three portions?"
It means they ate 2 portions. If they had instead eaten a double portion increase after already consuming a single portion, then they had 3 portions. The key difference is the word increase.
RE: percentages
"The final price was double the estimated price"
"The final price (cost ?) was twelve and a half times the estimated price."
I wish these fora had an "Instant Survey" function.
RE: percentages
Can't remember exactly the terms but in the analysis we used to do at my last place (UK) we used a factor.
The US companies we worked with used margin, the amount over.
We'd have a safety factor of 1.5 while they had a margin of .5.
Caused confusion at times.
RE: percentages
RE: percentages
My tri-fold wallet is designed to be folded in two places. When folded, it becomes three times as thick. Oh well, it's empty anyway.
RE: percentages
RE: percentages
For example, if you add 20% to a number, then subtract 20%, you don't end up with the original number, which can be confusing to the layman.
100 + 20% = 120
120 - 20% = 96
Go figure.
Don
Kansas City
RE: percentages
100+20%(of 100) = 120
120-20%(of 120)=96
RE: percentages
Out of curiousity I asked 3 people what they thought it meant. One person said it meant three times the original amount, the other two said it meant twice the original amount.
It's clearly a very bad phrase that should never be used.
RE: percentages
RE: percentages
RE: percentages
Actually we do not. Instead, 70% of the price we pay for our fuel is tax. In terms of additional cost, that's a 333% tax.
RE: percentages
RE: percentages
RE: percentages
The hardest/most comprehensive math was 'double A level'.
This came in 2 flavours. Pure and Statistics or Pure and Applied. Given my goal of being an Engineer and it's overlap with Physics I went for Pure and Applied. Pure and Applied was also widely considered more challenging than pure and statistics.
Funny thing was when those of us taking applied came to do the little bit of statistics (and probability) required as part of pure math we struggled. I can't recall the details but the irony wasn't lost on us!
RE: percentages
Naresuan University
Phitsanulok
Thailand
RE: percentages
"A maximum value for the setpoint is entered by the operator. If the calculated value is greater than the maximum value, the setpoint will be set to the maximum."
For the next sentence I am looking for an elegant way to say "if a tank is taken off-line the maximum value allowed will be 70% of what it was before when both tanks were on-line"
Would saying "the maximum value is reduced by 30%" be adequate or would that introduce confusion?
RE: percentages
My preference for indicating an increase would be "The actual price was 2.5 times the original estimate of $1". For a decrease, "It was half the original estimate of $1"; using a decimal "0.5 times" would be correct, but it would mentally bug a lot of people, technical or not.
Jim Sykes, P.Eng, GDTP-S
Profile Services
CAD-Documentation-GD&T-Product Development
www.profileservices.ca
RE: percentages
On a related note, we received a flyer from a local retailer in the mail yesterday advertising "an extra 20 to 10% off". That's not wrong, but I would have said "10 to 20% off". Or maybe that's how they say it in New York--the local (Chicago) retailer was just bought out by a New York company.
I know there are much greater problems in the world than this but it's nice to vent. I'm 1/5th less stressed now. That's a 20% reduction. Thanks!
RE: percentages
RE: percentages
Chris
Systems Analyst, I.S.
SolidWorks 06 4.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 06-21-06)
RE: percentages
RE: percentages
Chris
Systems Analyst, I.S.
SolidWorks 06 4.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 06-21-06)
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