can pass up to three reconciliation bills per year, with each bill addressing one of the topics of reconciliation (revenue, spending, or the debt limit). However, if Congress passes a reconciliation bill affecting more than one of those topics, it cannot pass another reconciliation bill later in the year affecting one of the topics addressed by the previous reconciliation bill. In practice, reconciliation bills have usually been passed once per year at most. Reconciliation cannot be used to enact or rescind discretionary spending (which is controlled through the annual appropriations process) or adjust Social Security spending, and is limited by the Byrd Rule, which allows senators to block provisions that are "extraneous" to spending, revenues, or the debt limit. Reconciliation was created by the Congressional Budget Act of 1974, and significantly altered with the introduction of the Byrd Rule in 1985 (amended in 1990). Originally infrequently used (it did not see first use until 1980). Rules by number There are currently forty-four Standing Rules of the Senate: SR Rule I: Appointment of a Senator to the Chair SR Rule II: Presentation of Credentials and Questions of Privilege SR Rule III: Oaths SR Rule IV: Commencement of Daily Sessions SR Rule V: Suspension and Amendment of the Rules SR Rule VI: Quorum – Absent Senators May Be Sent For SR Rule VII: Morning Business SR Rule VIII: Order of Business SR Rule IX: Messages SR Rule X: Special Orders SR Rule XI: Papers – Withdrawal, Printing, Reading of, and Reference SR Rule XII: Voting Procedure SR Rule XIII: Reconsideration SR Rule XIV: Joint Resolutions, and Preambles Thereto SR Rule XV: Amendments and Resolutions SR Rule XVI: Appropriations and Amendments to General Appropriation Bills SR Rule XVII: Reference to Committees; Motions to Discharge; Reports of Committees; and Hearings Available SR Rule XVIII: Business Continued from Session to Session SR Rule XIX: Debate SR Rule XX: Questions for Order SR Rule XXI: Session with Closed Doors SR Rule XXII: Precedence of Motions SR Rule XXIII: Privilege of the Floor SR Rule XXIV: Appointments of Committee SR Rule XXV: Standing Committees SR Rule XXVI: Committee Procedure SR Rule XXVII: Committee Staff SR Rule XXVIII: Conference Committees; Reports; Open Meetings SR Rule XXIX: Executive Sessions SR Rule XXX: Executive Session – Proceedings on Treaties SR Rule XXXI: Executive Session – Proceedings on Nominations SR Rule XXXII: The President Furnished with Copies of Record Executive Sessions