This is the 384th most frequent Icelandic word.
milljarðar
"Milljarðar" means "billions" in English.
In this sentence, 'milljarðar' (billion) is used in the dative plural form as it represents a number related to a quantity, specifically the revenue.
Útflutningstekjurnar námu fimm milljörðum íslenskra króna á síðasta ári.
The export revenues amounted to five billion Icelandic kronas last year.
Here, 'milljarðar' is in the nominative plural form because it refers to the number of people.
Það búa rúmlega sjö milljarðar manna á jörðinni.
There are just over seven billion people living on Earth.
In this sentence, 'milljarðar' appears in the dative plural form again because the number expresses an amount being spent.