What does it mean to settle social security mid-year

What does it mean to deduct the social security fee in the settlement of the total cost of the construction project?

A: Social security fees are calculated in accordance with the total cost of construction, construction unit settlement has included this number, but this cost should be borne by the construction unit and pay, so the construction unit settlement amount should be deducted in accordance with the provisions of the construction unit, left to the construction unit, so that they pay their own.

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