The tax increase comes as airlines face increased volatility in jet-fuel prices because of the crisis in Iraq, and as they continue to adjust to the decline in the value of the Canadian dollar, which has also hit airlines because the price of fuel is measured in U.S. dollars.

Setting aside whether it’s even a good idea to raise this particular tax – I have some doubts – if you replaced ‘decline’ with ‘increase’ in the quotation it would mirror previous complaints from airlines about raising taxes in the 90s through to today.