CREATE TABLE table_31483 ("Country" TEXT, "Number of Troops" FLOAT, "% of Total Troops" TEXT, "Troops per one million population" TEXT, "Troops per $1 billion  (  USD  )  GDP" TEXT)

Name the country for troops per one million being 54.9
SELECT "Country" FROM table_31483 WHERE "Troops per one million population" = '54.9'
SELECT "Country" FROM "table_31483" WHERE "Troops per one million population" = '54.9'