GST is only applied to the final consumption of goods and services, which means that savings and investments are not subject to this tax. This provides an incentive for individuals and businesses to save and invest their money, stimulating economic growth. Reduced Tax Evasion: GST helps to reduce tax evasion as it is collected at each stage of the supply chain. This makes it more difficult for businesses to avoid paying taxes, ensuring a more robust and efficient tax collection system calculate gst in nz.