Expats in Freetown/Sierra Leone

Hi everybody,
Does anybody have an idea how many expats living in Freetown area right now and Sierra Leone for that matter?
The National Tourist Board has told me, from April to September the total international experts that came to Sierra Leone is 228. But I would like to know how many living here and maybe expected the next year or so.
If it's not possible to get these information a qualified guess would also be nice:)
Best.
Palle