Augur is down to < 50 users.
https://thenextweb.com/hardfork/2018/08/20/dapps-userbase-dr...
https://thenextweb.com/hardfork/2018/08/20/dapps-userbase-dr...
This doesn't take into account users that made a bet in the past( most bets have long term horizons, >4 to 5 months) or users that have a current position but aren't betting anymore or users simply observing the markets( looking at a front end like predictions.global)
Also note that active users is probably not a great metric for this application, as it's not a consumer app/ time sink thing.
Money at stake is much a better metric
From predictions.global