If you make $ 10,000,000 a year living in Taiwan, you will be taxed $ 3,870,611. That means that your net pay will be $ 6,129,389 per year, or $ 510,782 per month. Your average tax rate is 38.7% and your marginal tax rate is 60.0%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of $ 100 in your salary will be taxed $ 60, hence, your net pay will only increase by $ 40.
A $ 1,000 bonus will generate an extra $ 400 of net incomes. A $ 5,000 bonus will generate an extra $ 2,000 of net incomes.