BART riders will only have one choice, starting later this year when the transit agency's paper tickets will gradually be replaced by plastic ones, according to an article in the Oakland Tribune. The BART board recently approved a $3.7 million contract to buy a five-year supply of the sturdier tickets, in order to reduce their susceptibility to being demagnetized. The new plastic tickets will be the same size and work the same way as current ones, however, they could still be demagnetized by a strong-enough magnet, according to a BART spokesman. The article says that about 250 riders a day have problems with their tickets. No word on how much it costs BART riders to ask station agents for help.