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Submitted on: 09 April 2015.
Revised on: 17 July 2015.
Accepted on: 13 September 2015.
___________________American Economic Journal-Applied Economics
Submitted on: 27 April 2016.
Revised on: 04 June 2016.
Accepted on: 28 June 2016.
___________________American Economic Journal-Applied Economics
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Submitted on: 04 August 2017.
Revised on: 03 October 2017.
Accepted on: 24 October 2017.
___________________American Economic Journal-Applied Economics
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