Complex sentence: However, the British Columbia HST was defeated in an August 2011 mail-in referendum by a 55% majority vote, and was converted to the old GST/PST system effective April 1,2013.
Split into simpler sentences: However, the British Columbia HST was defeated in an August 2011 mail-in referendum by a 55% majority vote. Conversion to the old GST/PST system was scheduled for April 1,2013.