How Often Is A Tax Ever Helpful To The Economy?

'Abolishing air passenger duty would create 91,000 jobs and add £4.2 billion to the economy in 12 months, according to a report.
The boost to employment and the economy would mainly come from increased passenger numbers following the removal of the airport departure tax, a report for the World Travel & Tourism Council (WTTC) said.'

http://money-news.money.aol.co.uk/article/2012/03/12/air_travel_tax_bad_for_economy