Table 6. Estimation of Tax Kuznets curve of Tax-to-GDP.

Year 2020	Official GDP	Actual TR	TKC approach Tax evasion	Tax evasion/GDP	Tax-to-GDP Curve shaped
TTR	19766240	2398667	190522	0.009638	N-shaped
DTR	19766240	1324208	134050	0.006781	N-shaped
ITR	19766240	1074459	43248	0.002187	N-shaped

Note: The data sources of GDP, TTR, DTR, ITR in Table 5 are derived from the data of DGBAS, Taiwan