Between 2008 and 2009, the data was collated on a mid-year basis, from June to May, but from last year Wrap decided to return to presenting it on a calendar year basis.

2008年至2009年间，收集数据是按照半年制进行的，从六月到下一年五月，但是去年开始，Wrap决定回归到历年制。

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Over the years, carmakers got away from the model-year calendar and started rolling out their latest designs on a staggered basis to keep consumers interested all year long.

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