Liberia as a country might have the highest percentage growth rate, what we’re dealing with here is ethnic groups within a country. The chareidi birthrate here and in Israel is among the highest in the world with an average of around 7 siblings per family which equals at least 3.5 percent growth using the most conservative estimates. documented Israeli statistics, which show between 4-4.5 annual growth rate for the chareidim community there.
EDITED, perhaps you are not aware that insulting remarks are not welcomed here