Just a quick note, it's a bit late now, but...
As I understand it, the oft-discussed tax change regarding corporate jets is to change the depreciation period for jets from 5 years back to 7. We were told that the impact on federal receipts would be small, something like $4 billion. But in fact, the REAL impact is less than 1% of that. Here's why.
Depreciation is a cost, which reduces the profits that jet owners pay taxes on. Suppose that you own a jet worth $1 million. Under the old law, you could depreciate $200,000 each year- 1/5 of the total. Under Obama's proposal, you could only depreciate 1/7 of the $1 million each year. That is $142,000. So you would have extra taxable income each year of about $60,000. 35% tax of that amount would equal about $20,000 in additional tax. HOWEVER, under the new proposal, at the end of five years you would still be able to claim a depreciation expense of $142,000 for two more years. So in the end, your tax deduction would be exactly the same, and the only benefit to the government would be that it would get its tax revenue two years sooner. What is it worth for the government to get the money sooner? Well, right now interest rates are about 0.5% for the two-year treasury. So, for our $1 million jet, the Treasury would get $20,000 extra for one year, which is worth $100. It would get another $20,000 for two years, which is worth a whopping $200. Total real benefit to the Treasury- $300. NOT $40,000. So the real financial benefit of the change in the depreciation schedule is less than 1% of what the Treasury says it would be! Using bigger numbers, if the Treasury says they will collect $4 billion extra, then the actual value of the depreciation change is 3/4 of 1% of that amount. Which is about $30 million.
By the way, there's another important assumption in here. I assume that the corporations which own the jets would pay the maximum tax rate of 35%. If they don't for any reason, then the benefit to the Treasury would be smaller still.