Taxation (Gnp Percentages) 68. Mr. Dixon asked the Chancellor of the Exchequer what percentage of gross national product was represented by taxation in 1964; and what was the comparable percentage in 1969. Mr. Maurice Macmillan In 1964 total taxation amounted to 33·2 per cent. of the gross national product at factor cost; in 1969 the corresponding percentage was 44·2.