A quote from The Guardian:

Last year, a paper in Nature co-authored by Sir David King, the UK government's former chief scientific adviser and currently the government's climate change envoy, concluded that a "tipping point" in the global oil supply had been reached since 2005, with global conventional production hitting a ceiling of around 75 million barrels per day (mbd) despite price increases of 15% a year.

Is that proper grammatical usage of tense? "Had been reached" seems to stand for Past Perfect; yet since, to my taste, implies an ongoing process and hence seems to call for Present Perfect Continuous (as in "The reactor has been in operation since 2005" or "I've been trying to understand English grammar since God knows when").

  • 5
    (opinion) It doesn't sound quite proper to my ear. But it's understandable.
    – user230
    Nov 19, 2013 at 17:38
  • 2
    Agree with snaiboat. This is passable. I would not conclude from the usage that the user is not a native speaker, or not highly literate or anything of the sort.
    – Kaz
    Nov 19, 2013 at 22:56

3 Answers 3


As emrys says, it is the since which is awkward here.

I think what the Guardian author means is that the tipping point was reached not in 2005 or at some specific point since 2005, but in the years since 2005. This would reflect what Murray and King said in the 2012 Nature paper: "In 2005, global production of regular crude oil reached about 72 million barrels per day. From then on, production capacity seems to have hit a ceiling at 75 million barrels per day."

But the past perfect is correct here; the author is referring to what was said a year ago by Murray and King, who were referring to the years between 2005 and 2012. The title of the Murray/King paper at that time was in the present perfect: "Climate policy: Oil's tipping point has passed".


A past perfect like "had been" requires a reference which is in the past tense.

So neither of these is strictly correct, even though the second one places the tipping point into the past relative to 2005:

The tipping point had been reached since 2005.*

The tipping point had been reached prior to 2005.*

The second sentence can be corrected very simply like this:

The tipping point was reached prior to 2005.

To retain the "had been", we need something in the past, such as:

The tipping point had been reached by the time 2005 rolled around.

It was noted by researchers in 2005 that the tipping point had already been reached.

To fix the first sentence, we use the plain past, and eliminate the akward preposition "since":

The tipping point was reached (sometime) after 2005.

The problem with "since" is that it indicates ongoing events which take place from some point in time, onward. A tipping point is a well-defined moment in time: it does not take place since anything.

He's been a professor of English since 2005.

He's been a professor of English after 2005. *

The tipping point occurred since 2005. *

The tipping point occurred after 2005.

Now, there is a meaning of since where it is used to indicate that new events have taken place after some point, and those events are not continuous from that past point onward. Example:

Since 2005, there { have been | were } several accidents at the ABC industrial plant.

The difference is that this indicates a potential for something repeated or habitual. Reaching a tipping point is not habitual; it's a one-time event. We can create the impression that reaching a tipping point can be repeated:

The tipping point { was | has been } reached { once | twice | several times | ...} since 2005.

Now it is grammatically correct, believe it or not. One more example with the industrial accident sentence exposes how subtle then nuance is:

Since 2005, there was an accident at the ABC plant.*

Since 2005, there was one accident at the ABC plant.

Sometime after 2005, there was an accident at the ABC plant.

The first sentence may be accepted by some speakers, but reported as odd or questionable by others.

It may seem we have digressed from the "had been since 2005" topic! However, the nuances of "since" are relevant to it.


No, it doesn't seem correct for exactly the reasons you stated. Since a tipping point is a fixed point in time instead of an ongoing process, a more natural way to write this would be a "tipping point" in the global oil supply was reached in 2005.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .