I just came across this post by Paul Graham called, "modeling a wealth tax." It's from last year, but it recently resurfaced. In it, he paints a scenario. Let's say you're a successful entrepreneur in your twenties (i.e. you make some money) and then you live for another 60 years. How much of your stock would the government take with various wealth taxes?
With a 1% wealth tax, it means that you would get to keep 99% of your stock each year. But assuming the wealth tax gets applied every year, you would be left with 0.99^60, which equals 0.547. Put more simply, a 1% wealth tax would mean that over the course of the 60 years after you built your company, you would be giving the government 45% of your stock.
How did this number get so big?
The reason wealth taxes have such dramatic effects is that they're applied over and over to the same money. Income tax happens every year, but only to that year's income. Whereas if you live for 60 years after acquiring some asset, a wealth tax will tax that same asset 60 times. A wealth tax compounds.
Of course, Paul also points out that giving away a portion of your assets each year doesn't necessarily mean that you're becoming net poorer, so long as your assets are increasing in value by more than the wealth tax rate.
Still, these are massive numbers. A 2% wealth tax would translate, over this same 60 year time period, into the government taking 70% of your stock. A 5% wealth tax works out to 95%. For more on this, check out Paul Graham's post.
