Odds of Hanging On
Occasionally, missionary workers are called back to their home countries due to political instability or an outbreak of violence. But don't let that be your biggest worry. (Definitely let it be a big worry. Just don't let it be your biggest.)
Because the biggest obstacle you face in completing your time as a missionary is actually you. Though there aren't specific numbers, a good percentage of missionaries end up so discouraged that they return home before their service is scheduled to end.