An estimated 40.3 million people were victims of modern slavery in 2016, a quarter of them children, according to new global slavery statistics released today.
Be wary of that number, this includes a very wide definition indeed. However:
The 2017 Estimates of Modern Slavery report calculates that of 24.9 million victims of forced labour, 16 million are thought to be in the private economy, 4.8 million in forced sexual exploitation and 4.1 million in state-sponsored forced labour including mandatory military conscription and agricultural work.
Conscription is slavery. Those who advocate mandatory national youth schemes and the like should take note.