I believe the real supply is around 2.3M since 1.6M sell wall will be eventually burned.

The amount of staked LEO is currently: 2,242,795.82 LEO.

That's 54.01% of the circulating supply if you factor in the sell wall.

Technically, the sell wall doesn't really count as those tokens will likely never see the light of day. So if you remove the 1.6M tokens still remaining in the wall (which will be completely burned in 8 months), then the actual staked number looks more like this.

Source: https://steempeak.com/steemleo/@steem.leo/steemleo-burn-report-2-we-ve-burned-half-a-million-leo-already