Chema Nieto Castañón Apr 28, 2019:

I trust you here, Neil.
Your link does specify though that conclusions can be expressed in present tense;
Use the present tense to express general truths, such as conclusions (drawn by you or by others) and atemporal facts (including information about what the paper does or covers). 
This is what I first read. But rereading I fully see your point;
A survey showed that 1.5% used...

The Spanish rendering might suggest that the results of the survey are taken as fact here -hence the present tense in Spanish also- and so maybe there is space for discussion anyhow (depending on the original context). No matter what, clean and clear; thanks a lot for your comment and for the link!

Neil Ashby Apr 28, 2019:

The main reason to change the tense is that good scientific writing in English always uses the past simple for the method and results.
https://www.nature.com/scitable/topicpage/effective-writing-...

Neil Ashby Apr 28, 2019:

Chema Study methods and results are always reported in the past tense in English. I think we'd use the past perfect to compare a long-gone habit with a current habit, although there is no suggestion that the text is making any such comparison.

Chema Nieto Castañón Apr 27, 2019:

use vs. used As for present versus past tense (usa vs. usaba), the original present tense conveys the ides of an actual trend of the population being surveyed. I would use present tense in English as well -although past tense might be understandable as Neil puts it; i.e. the survey showed x% (of the population) used a fountain pen. Reading it in past tense though sounds misleading, as if the survey had studied a long gone habit versus an actual one.

Chema Nieto Castañón Apr 27, 2019:

use vs. uses As for the English "use" versus "uses" in this case it depends on how do you read that 1.5% and what PP is. Even though there is no doubt in Spanish as to how and when to use the singular (usa) versus the plural (usan), collective nouns in English follow a particular form of agreement sometimes called notional agreement.

As Merriam-Webster’s says, the principle of notional agreement “is simple: when the group is considered as a unit, the singular verb is used; when it is thought of as a collection of individuals, the plural verb is used.”
https://www.grammarphobia.com/blog/2010/08/collective-bargai...

And so, in spite of clearly reading "el 1.5 por ciento (de la población)" as the "singular" subject of the Spanish original I am not so sure after all whether you should use the singular (uses) or the plural (use) in this phrasing in English. Some specific context might help.

One more example;

One third of the world’s population consumes/consume two thirds of the world’s resources.
https://www.oxfordlearnersdictionaries.com/definition/englis...

Chema Nieto Castañón Apr 25, 2019:

Se refiere al 1.5% de la población (de ahí el singular "usa" versus "usan"). Sea lo que sea PP, el original dice que, a partir de los datos obtenidos en la encuesta, puede concluirse que el 1.5% de la población del Reino Unido utiliza PP (en la actualidad).