Why is it that the preferred stockholders equity section of the balance sheet changes only when new

Question:

Why is it that the preferred stockholders’ equity section of the changes only when new shares are sold or repurchased, whereas the common stockholders’ equity section changes from year to year regardless of whether new shares are bought or sold?
Balance Sheet
Balance sheet is a statement of the financial position of a business that list all the assets, liabilities, and owner’s equity and shareholder’s equity at a particular point of time. A balance sheet is also called as a “statement of financial...