1. A moving picture coding method for calculating a motion vector predictor to be used when coding a motion vector of a current block to be coded, and coding the current block, to generate a bitstream, the method comprising: deriving each of one or more first motion vector predictor candidates, based on a motion vector used for coding a block spatially or temporally adjacent to the current block; deriving one or more second motion vector predictor candidates each having a predetermined vector as a motion vector; selecting, from among the one or more first motion vector predictor candidates and the one or more second motion vector predictor candidates, the motion vector predictor to be used for coding the motion vector of the current block; and adding an index for identifying the motion vector predictor to the bitstream.