A partner or member of an association shall report his share of the net income of a partnership or association for its taxable year ending within or with the taxable year of the partner or member. The share of a partner of the net income of a partnership shall include his share of any guaranteed payments received from the partnership. The share of a partner of income shall be reported as net profits from the operation of a business, profession or other activity, net gains or income from disposition of property, net gains or income derived from or in the form of rents, royalties, patents and copyrights, dividends, interest, gambling or lottery winnings, or net gains or income derived through estates and trusts, depending upon which class it shall fall within.
61 Pa. Code § 107.1