# percent of the time

New Use of A.I. Accurately Detects Cancer 86 Percent of the Time link

1.In this sentence, what prepositions can be inserted before "86 percent of the time"?
For example, "for 86 percent of the time", "at 86 percent of the time", or else???? I want to know all of the possible prepositions.

The reason why I ask this is that I want to understand it more accurately. I assume "86 percent of the time" is used like an adverb. So if I know all of the prepositions which can be used before "86 percent of the time", it will be very helpful to understand the meaning of the phrase.

In the case of using the phrase with "for", I feel confused because I think "for" means "a length of time", but it seems to me that the meaning of "a length of time" doesn't fit in well with the rest.

1. Which meaning in this dictionary "time" in OLD does "time" come under? #5,#6, or #8? I cannot reach a conclusion.
• No prepositions are required before 86% of the time. The figure is used in the sense of most of the time / all of the time Jul 31, 2020 at 8:48
• @RonaldSole Thank you for your answer. I know that any prepositions are not required. But if you insist, what prepositions are acceptable though they may seem a little bit unidiomatic? Why I say this is that I can google some like "for XX percent of the time" Jul 31, 2020 at 9:11

You shouldn't use any prepositions before that phrase because it is a fixed idiom. You are correct that it is adverbial. It is comparable to "all (of) the time", as in this definition:
Merriam-Webster "all (of) the time"
"1 : on every occasion : always"

"All of the time" means "always" or, "in every case". The opposite is "never", or "in no case". For things in between the extremes, we can say "x percent of the time".

This idiom is related to the use of "time" to mean "instance" or "occasion", but it uses "time" in singular form, not plural. One doesn't say "86 percent of the times".

The meaning in your example is that the application of A.I. correctly detects 86 percent of cases of cancer that it is presented with.

• Thank you for your answer. I know that any prepositions are not required. But if you insist, what prepositions are acceptable though they may seem a little bit unidiomatic? Why I say this is that I can google some like "for XX percent of the time" Jul 31, 2020 at 9:10
• I believe the phrase "for 100 percent of the time" may be a different usage, actually referring to a span of time, There are also some false hits, such as "...accounted for 100 percent of the time", where the word "for" is part of the phrase "accounted for". In the use you asked about, "for" is not correct. Jul 31, 2020 at 9:23
• How about this one? : "The study has also found that being sad for ten percent of the time is actually good for you." link Jul 31, 2020 at 17:26
• @Mcreaper That is, in fact, a description of a percentage of actual time, and not a percentage of cases or instances. Even in that use, "for" is unnecessary. Jul 31, 2020 at 18:00
• By the way, there is a way to use Google ngram viewer to search for phrases with parts of speech, You might look for instances of a preposition followed by the phrase you are interested in. Jul 31, 2020 at 18:04