TAXATION. INITIATIVE CONSTITUTIONAL AMENDMENT. Amends Article XIIIA, enacted as Proposition 13 in 1978, by adding additional restrictions on real property taxation and on enactment of new tax measures. Designates various effective dates for provisions. Prohibits imposition of any new tax based upon real property ownership, sale, or lease. Prohibits adoption of measures which increase any tax on any taxpayer except upon two-thirds vote of Legislature for state taxes and two-thirds vote of electorate for other governmental entities. Provides for specified refunds including refunds of real property taxes attributable to assessed value inflation adjustments in assessment years 1975-76, 1976-77, 1977-78. Summary of estimate by Legislative Analys...