Numbers only get reported when an electoral district has finished counting. Right now only 5 of 382 districts have reported (and they're mostly small districts, which is why they finished counting so quickly).
So are we expecting tens of millions to vote by the end?
Edit: I did some math and figured it out. Thanks for the help, hehehe
Somewhere around 25-30 million, I think.
"16.8 million votes needed to win referendum" - so there would therefore be ~33.6 million votes in total.