Accumulative Man Hours

This is a sign at the entrance to a construction site on West Coast Road at Clementi Woods Park.

I’m happy that there have not been any accidents. I know that because the number of accidents is zero, and also because the number of hours and the number of accident-free hours are the same.

What they call the number of hours, however, is hilarious. See below for why I think so.

Accumulative vs Cumulative

“Accumulative” looks to me like an accidental portmanteau of two perfectly good, relevant adjectives with similar meanings: “cumulative” and “accumulated”.

The word “accumulative” is a “real” word (whatever that means) with recorded uses going back to the 1600s, but as far as I’m concerned, there may as well be no such word as “accumulative”. We just use “cumulative”.

According to actual data, “cumulative” is the preferred form; it’s forty times as common as “accumulative”.

Google Books Ngram Viewer

Although past performance is no guarantee of future performance, the proportions don’t seem likely to change much anytime soon.


I saw the word “accumulatively” in an article I was editing in 2009 that was written in English by a Chinese person in China. The word struck me as extremely odd, and I changed it because the only use of it I could find when I did a search online was a 1955 patent for “Accumulatively resisting and snubbing becket hitches“.

That patent title is like a piece of postmodern poetry. Take a moment to appreciate it.

Accumulatively resisting and snubbing becket hitches.

It’s mysterious; it’s musical; it sounds like it means something, yet it lies completely outside my own personal experience. The image in the patent is reminiscent of a diagram of some kind of boy-scout knot. I have heard of knots called “hitches”, but not “becket hitches”, and what it means for a kind of knot to snub something (accumulatively or otherwise) I can’t quite imagine.


We’ve seen the sign, heard the story, inspected the data, and even tried to imagine a knot that can resist and snub. Should the word “accumulative” be on the sign or not?

My browser’s spell-check accepts “accumulative” but not “accumulatively”, so perhaps I, too, should be accepting of the adjective.

Still, I vote no.

You could argue that the construction project is managed by engineers, who are the same kind of people that write patents, thus this is a legitimate situation in which to use the word. However, I assume the sign is supposed to be read by the public, not engineers.

The sign could just say “Total Man Hours”, but that might imply (wrongly) that the project had been completed. Really the intended meaning is “Total Man Hours… So Far”.

“Cumulative Man Hours” is probably best.