Funding for this research was provided by:
Ministry of Science and Technology, Taiwan (NSC 103-2410-H-022-011-)
Received: 24 January 2018
Accepted: 5 October 2018
First Online: 19 October 2018
Ethics approval and consent to participate
: This article does not contain any studies with human participants performed by any of the authors. Euromonitor International has authorized the authors to use its data in this study.
: Not applicable.
: The authors declare that they have no competing interests.
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