Originally launched in 1997, the three generations of Toyota's signature hybrid vehicle, the Prius, together have surpassed 3 million units sold worldwide as of the end of June, 2013 Toyota announced today.

The second generation of the Prius was introduced in 2003 and sold nearly 1.2 million units, followed by the current model unveiled in 2009, which has sold 1.69 million through June. North America remains a significant market for the Prius, accounting for approximately 76% of all Prius sales outside Toyota's home country of Japan.

According to Toyota, costs associated with the hybrid systems used in the Prius have declined by two-thirds, in addition to a nearly 36% improvement in fuel economy since the first-generation Prius rolled off the production line.

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