Complex sentence: Some forms of interest on loans, and most capital gains on financial assets and property are also excluded; therefore, transfers are flows of income and expenditure are regarded as unrelated to production and to the value of new output.
Split into simpler sentences: Some forms of interest on loans, and most capital gains on financial assets and property are also excluded. So transfers are flows of income and expenditure regarded as being unrelated to production and to the value of new output.