According to the Singapore government, "Net Investment Returns Contribution" is the return from only two of the funds that manage Singapore's reserves. "Singaporeans benefit from the investments of GIC and Temasek as they supplement the annual Budget through the Net Investment Returns Contribution (NIRC)."
The "Net Investment Returns Contribution" is $7.35 billion for FY2010 and $7.78 billion for FY2011.
Note that the "Net Investment Returns Contribution" is not the return from the full reserve amount. The Monetary Authority of Singapore (MAS) manages a fund that is even bigger than Temasek. ""MAS and Temasek publish the size of the funds they manage. As of 30 April 2012, the Official Foreign Reserves managed by MAS was S$304 billion, and as of 31 March 2012, the size of Temasek’s portfolio was S$198 billion." http://app.mof.gov.sg/reserves_sectionone.aspx And there are many other funds where the numbers are not clearly reported. NIRC is not even the full amount that GIC and Temasek made. "The Net Investment Returns Contribution (NRIC) of about $7 billion is drawn from returns on assets in excess of the liabilities and not gross assets".
Therefore, $7 billion is an underestimate of how much the Singapore government gets from its fund investment activity.
If Singapore were a citizen-ownership democracy, its citizens (3.2 million) would have received $2297 in 2010 and $2431 in 2011 per citizen. This amount is just from part of the investment of the reserve - the part that is often called its sovereign wealth fund.
For a small family of 4, this amount would had been $9187 in 2011 and $9725 in 2011.
Remember that citizens own all the country's common wealth that has not been sold to private entities. There are many common properties that have not been counted in the above estimate.