California Constitution Art. XIII B, § 5

Each entity of government may establish such contingency, emergency, unemployment, reserve, retirement, sinking fund, trust, or similar funds as it shall deem reasonable and proper. Contributions to any such fund, to the extent that such contributions are derived from the proceeds of taxes, shall for purposes of this Article constitute appropriations subject to limitation in the year of contribution. Neither withdrawals from any such fund, nor expenditures of (or authorizations to expend) such withdrawals, nor transfers between or among such funds, shall for purposes of this Article constitute appropriations subject to limitation.