Calcualte national income from the following data:
(i) Compensation of employees 400
(ii) Profits 200
(iii) Rent 150
(iv) Interest 100
(v) Dividends 120
(vi) Employers contribution to social security schemes 40
(vii) Mixed income of self-employed 500
(viii) Direct tax 100
(ix) Net factor income from abroad (-)50