Singapore's residential rents are falling at a precipitous rate - and the reason could be a sea-change in the make-up of the city-state's expat workers.

The drops in Singapore's residential rents has - mistakenly - being attributed to the government turning off the spigot of foreign workers flowing into the country. In fact, the number of foreign workers continues to rise, with the figure, excluding domestic helpers, up more than 22,000 last year, according to data from the Ministry of Manpower. While the growth rate has certainly tapered down from a peak of nearly 149,000 added in 2008, those fresh additions will still be looking for housing.