According to the latest SIA Engineering Company annual report, their 6200 employees cost about SGD500 mil. SGD80,000 per annum, or AUD71,000 at current exchange rates. Are SIAEC's labour costs really lower than the US (doubt it) or Australia? If the AUD depreciates a further 10% against the SGD to parity, I'm sure any labour cost advantage SIAEC ever had would evaporate.
I doubt that labour costs alone are everything.