From http://hagstofan.is/Hagtolur/Mannfjoldi, which is the population section of Hagstofa Íslands, which in practice roughly means the National Statistical Bureau of Iceland, although the name means the Economic Institute of Iceland - and they are indeed concerned the economy, but also the national register. That leads to this quote:
"Í lok 4. ársfjórðungs 2014 bjuggu 329.040 manns á Íslandi ..."
which means "At the end of the last quarter of 2014 Iceland had 329,040 inhabitants."
Look up http://www.ethnologue.com/country/IS and you will find an an alleged population of 381,400.
Look up http://www.ethnologue.com/language/isl and you will find the resident Icelandic speaking population given as 230,000 and the total for all countries as 243,840.
The figure 230,000 seems to be a leftover from the sixties or seventies.
There is a English version of the Statistical Bureau here: http://www.statice.is/
You can gather all the relevant information there, but the current figures you give are incredibly wrong,
All the best