1. According to the current calculation method:

Monthly tax =8400-3500=4900 tax rate 20%

Monthly personal income tax =4900*20%-555=425

Year =425* 12=5 100.

Year-end bonus/12=4083 tax rate 10%

Taxable amount = 49000 *10%-105 = 4795.

Total tax payment =5 100+4795=9895

2. Divide the year-end bonus to each month, then the monthly taxable salary =4900+4083=8983, and the tax rate is still 20%.

Then the monthly tax payment = 8983 * 20%-555 =1241.6.

Total tax paid =1241.6 *12 =14899.2

It can be seen that the average distribution has paid more taxes every month.

3. If the monthly taxable salary is reduced to 4,500, the year-end bonus = 400 *12+49,000 = 53,800.

Then the monthly personal income tax = 4500 *10%-105 = 345.

Annual =345* 12=4 140.

Year-end bonus/12=4483, and the tax rate is still 10%.

Year-end bonus tax = 53800 *10%-105 = 5275.

Total tax payment =4 140+5275=94 15.

Therefore, the personal income tax is the lowest when the monthly salary is 8000 and the year-end bonus is 53800.