countywide sales tax by a half-cent to fund future transit plans. In April 2020, MTS decided not to pursue the transit tax ballot initiative. Fleet The San Diego Trolley operates on all its main lines with an all-Siemens fleet of light-rail vehicles (LRVs). It also runs 2 "heritage" PCC street cars on the Silver Line, a downtown-only circuit on a select schedule. When the system opened in 1981, the agency purchased a fleet of 71 high-floor Siemens–Duewag U2 vehicles, originally designed for and used by the Frankfurt U-Bahn. At the time, no purpose-built LRVs were being manufactured for the North American market, so the model was adapted for use by San Diego and other transit systems in Canada. The vehicles were built in West Germany, with some assistance from a Siemens facility in Florin, California, a suburb of Sacramento. These cars were withdrawn from service between 2010 and 2015. Eleven of the U2 cars were sold to the new Metrotranvía Mendoza in Mendoza, Argentina in 2010, 29 were retired after the Orange Line was converted in early 2013, and the rest were retired after the Blue Line was converted in January 2015. Six U2 cars have been preserved: car 1001 was retained by MTS for use on the Silver Line, cars 1003 and 1008 were donated to the Southern California Railway Museum, cars 1017 and 1018 were donated to the Western Railway Museum, and car 1019 was donated to the Rockhill Trolley Museum. Car 1035 was sold in late 2020 to the Memphis Area Transit Authority, which operates a vintage-trolley system and intends to use the LRV for testing of modern, higher-capacity vehicles on its Madison Avenue Line. In 1995, the San Diego Trolley purchased a fleet of 52 high-floor Siemens SD-100 vehicles, an evolution of the U2, but redesigned for the North American market. Starting with this order, all of San Diego's future LRVs would be built in California at the Florin factory. Starting in 2005, San Diego started shifting to a low-floor fleet. The design of the Siemens S70 vehicles required that stations be designed with slightly higher platforms, so the 11 car fleet could only operate on the newly constructed Green Line. The other limitation of the S70 fleet was that they were about longer than the SD-100 vehicles, which would make three-car trains longer than a single block in Downtown San Diego. In 2009, San Diego