Why would you deliver a video in 1920x964? Quite simply; I've never come across this aspect ratio in video before and I just wanted to know if there is a standard in video (that I'm unaware of) that routinely uses this aspect ratio.

For a little extra background: an outsourced company in the States produced a video for us (we're based in the UK) and they delivered the video in 1920x964 and I really don't want to go back to them and ask 'why?' in case I seem like an idiot, so I'm checking with you gals and guys first :D

I know I've never heard of that ratio but I didn't know if it were more standard either in the US or in a different branch of film-making that I'm not party to.
I cannot think of a good reason why 1920x964.  It is not uncommon to see 2:1 aspect ratios, which would be 1920x960.  The extra 4 pixels are a mystery, especially because 960 divides by 8 and 16, which make it very JPG friendly.  964 does not divide evenly by 8, either.