The US has a very high tax compliance rate because most of our income is reported through 3rd parties (w2, 1099, etc.). For income that is not reported through a 3rd party, we have low compliance rates as well. For income subject to little or no information reporting, the misreported income is 63% of total according to the IRS. https://www.irs.gov/pub/irs-soi/p1415.pdf