El Salvador is 91% larger than Jamaica.
Area: 10,991 km2 World Factbook
Population: 2,930,050 (July 2014) World Factbook
Jamaica is an island country situated in the Caribbean Sea, comprising the third-largest island of the Greater Antilles. Wikipedia
Area: 21,041 km2 World Factbook
Population: 6,125,512 (July 2014) World Factbook
El Salvador, officially the Republic of El Salvador, is the smallest and the most densely populated country in Central America. The country's capital city and largest city is San Salvador. Important cultural and commercial centers for Central America on the whole include Santa Ana and San Miguel. Wikipedia