Why is Shanghai social security more than 2000 a month?

The exchange base is high, which is a high income level. Shanghai social security deducts 2000 yuan per month, which is a high income level. Social security includes five types of insurance: basic old-age insurance, basic medical insurance and unemployment insurance. The proportion of individual contributions is 8%, 2% and 0.5% respectively. According to this rate, the monthly payment base is about 19050 yuan. The monthly payment base of that year was the average salary of the previous year, and the monthly deduction of social security was quite high.