Why exactly is social security excluded from accounting the GDP?

Question

thx

Answer 1

Transfer payments like interest on the debt and social security are counted as personal income on the income accounts but since they neither add value or produce any thing they are not counted in the product accounts. GDP is an aggregate number so who gets the income does not matter.
http://www.bea.gov/newsreleases/national/pi/pinewsrelease.htm

Answer 2

Like meg said it is a transfer payment. Social security gets accounted for in GDP when the recipients spend the money on goods and services.

Answer 3

GDP or Gross Domestic Product is the total amount of output which includes goods and services produced in a country over a given period of time which is usually one fiscal year.
total output=total income=total expenditure.
any expenditure made on any commodities is an income of the producer.so it could be said that any payment made is exchanged with a good or service.
social security is a payment made by government.here the payment is made without any return of service from the receiver.thus expenditure which do not result in production are excluded from GDP.