Do you have any sources to back up your numbers?
88% of foreign box office revenues from 3D seems highly unlikely. Maybe 88% of 3D movies as there usually isn't a choice, just as with Gravity which had about 90% of it's screenings in 3D, with 2D only being shown at akward times, and IMAX 2D was not even an option. Actually before Gravity 3D revenue hit an all time low: http://insidemovies.ew.com/2013/08/09/3d-movies-box-office/

Plus Gravity's success did not carry over to other movies, which are back down to the usual 30% to 40% 3D revenue share
http://www.thewrap.com/thor-the-dark-world-3d-gravity-marvel-disney

http://www.rollingstone.com/movies/news/can-gravity-save-3d-20131012
Gravity actually had the biggest effect for IMAX with 21% of it's revenue coming from the very low number of IMAX screens.

The 80% of Gravity doesn't mean much unless you actually have a choice at the 8pm and 10pm screenings to also see the 4K 2D version. It's like saying home 3D is doing great since most tv's sold nowadays include some form of 3D capability. Then look at the 3D blu-ray percentage share and it drops down to a niche market. At best a highly anticipated 3D blu-ray movie can get 20% unit share of blu-ray sales, usually it's down into the single digits, and that's a percentage of the on average 40% to 50% blu-ray sales as opposed to total physical movie sales. So in the very best case you're looking at 10% of physical movie buyers opting for the 3D version.

Amazon having sales on 3D movies as low as $14.99 is also a sign that sales are not meeting their projections.
I have a couple 3D blu-ray movies as well, simply because the price was the same for 2D or 3D. Can't hurt to have the extra disc in case I end up with a 3D capable tv. I have the 2D version of Gravity pre-ordered though, not worth the extra $5. But it will be interesting to see how that 80% of Gravity in the cinema translates to 3D blu-ray sales.

I can see Godzilla 3D doing more for both 3D & IMAX then Gravity ever did.....for obvious reasons.