What is the total monthly social security salary?

Last month's financial statement total wages = last month's total wages, this month's reduction of total wages = less wages than last month.

It means the total amount of insurance, so it should be counted from the month when he officially joined the insurance. Generally, the social security audit will last for three months, because sometimes there will be internships or probation periods. Generally speaking, if the underreporting is not too outrageous, there is no need to pay social security.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.