Need a term to describe a trend

[lingyai]

Sorry, this is a basic question. I'm looking for a term which describes the following kind of trend.

Let's say a value in a time series peaks at a rate of 100 in the third year. The rates during the build-up phase are 50 in Year 2 and 25 in Year 1. In other words, during the build-up up to and including the first year of the peak, a predecessor is always half of its successor.

I'd be grateful for any help.

 

[Denis]

"Double your money, double your fun" :idea:

 

[lingyai]

You're a real asset to the forum, D. Any serious replies?

 

[stapel]

You're a real asset to the forum, D. Any serious replies?

Yes, Denis is quite an asset. Sometimes his sense of humor can get a bit carried away, but I'm not sure what the problem is here. If the previous amount is always half of the next amount, then the "next" is always double the previous.

Did you have something specific in mind? Asking for "a term" is a bit vague....

Thank you.

Eliz.

 

[lingyai]

Yes, well I'm sure once one gets to know him...

To answer your question: I'm writing documentation for a model, trying to keep it concise. One of the assumptions is that a certain trend behaves the way I described . I'd just like to describe it more succintly.

 

[stapel]

If an amount doubles (or triples, etc) in a fixed amount of time (every ten minutes, every year, etc), then the growth is, by definition, "exponential". So you might use that term to describe the growth pattern during your "build up" period.

But that's just a guess, because exponential growth doesn't have a "peak" after which everything levels out. (That would be more rational or logarithmic.)

Eliz.

 

[wjm11]

Perhaps you are looking for the term "doubling time" (in this case, one year) which is often used to describe the exponential growth of bacteria, among other things...

 

[lingyai]

Thank you both.