Senator Brian Schatz (D-HI) and Congressman Peter DeFazio (D-Ore.) have introduced legislation that would institute a financial transactions tax of 0.1 percent on the sale of any stocks, bonds, and derivates.

A financial transactions tax would be a terrible idea and has failed when it has been tried before. It would restrict economic growth and investment and would fail to raise revenue as supporters claim. 

A financial transaction tax would harm investment & economic growth

This tax would have broad, negative economic effects. On a macroeconomic level, this tax would increase the cost of capital and reduce productivity which would in turn harm wages and jobs. 

This tax would also increase market volatility as there would be fewer buyers and sellers and therefore more price jumps.

An FTT would especially impact fund managers that are responsible for 401(k)s, pensions, and index funds and make frequent trades. As a result, returns on pension funds and other savings would be lower because of the increased the costs of buying and selling and the reduction in value of shares.

In fact, BlackRock has previously estimated a financial transaction tax of 0.1 percent would result in an investor losing $2,300 in returns on a $10,000 investment in a global equity fund over ten years.

A financial transactions tax is bad tax policy

Ideal tax policy should be economically neutral by taxing income once (ideally at the point of consumption).

However, the FTT would be an additional layer of taxation on top of existing capital gains taxes, individual income taxes, and corporate taxes. 

Because it is levied on a transaction, this tax could be imposed on the same financial instrument multiple times. In addition, the FTT would often be imposed at the same time as the capital gains tax – tax would be paid on the act of selling the asset and also on the gain of the asset.

A financial transactions tax fails to raise the revenue supporters claim

Because it would result in less trades and cause capital to flee, this tax would have the flow on effect of reducing income tax and capital gains tax revenue. 

Case in point – an analysis by the Congressional Budget Office found that imposing a FTT would “decrease the volume of transactions and would make some types of trading activity” and “probably reduce output and employment.” 

In fact, some have predicted that a financial transactions tax would raise little, if any net revenue because of these negative impacts.

A financial transactions tax has failed in the past

In 1984, Sweden imposed a financial transaction tax, a proposal that lasted just six years. Even though investors were restricted in moving capital to foreign markets, most trading migrated to London to avoid the tax. 

Not only did this mean the FTT raised little revenue, capital gains tax revenue dropped because of a reduction in sales. When it was abolished in 1990, investment began to return to Sweden.

This is not an isolated incident.

When Italy and France imposed FTTs in 2012, both countries raised less than a quarter of expected revenues.

study of New York State’s FTT that was in effect between 1932 and 1981 found that the tax increased the cost of capital, reduced trading and increased market volatility.