Which country has the most efficient missionary-sending church?

"One might guess Korea (16,000), the Philippines or Norway...But the surprising fact is that Mongolia tops the list as the most efficient missionary sending country. One out of every 222 Mongolian believers serves with a mission organization. In fact, of the entire global Protestant community, the most efficient missionary-sending countries are not wealthy ones....If Mongolia can send one missionary for every 222 believers, other countries are without excuse."

("The state of the Gospel" Jason Mandryk, 2006 speech -Perspectives, 4th ed 2009 Winter, William Carey Library, pg 365)