I've always assumed that these eye-boggling numbers are almost certainly wildly underestimated, because only a few companies actually bother to report anything. Yesterday, an anonymous person left a comment suggesting that it might be interesting to have a look at NYSE Liffe. So, I did.
Good news, NYSE Euronext does actually report the value of the transactions they handle, and you don't even have to pay them to get access to their numbers! You can find the numbers here. As an illustration, here are the numbers for just one day - the latest one, namely the 11th January 2012. The values are in Euros
The figures show that NYSE Liffe managed to handle over 2 trillion euros worth of transactions in just one day. 97.96% were Short Term Interest Rate Products. The other areas are trivial. Obviously, traders are not interested in medium and long term interest rates (1%) - they are clearly just trying to make a fast buck. And equities (0.96%) and commodities (0.06%) are also hardly worth bothering with. And when we compare the 6 different Euronext sites (Amsterdam, Bclear, Brussels, Lisbon, London and Paris) it is clear that the others might as well not bother - London did 99.36% of the trading.
So, with around 250 trading days per year, I think we can assume that a nice round 500 trillion euros can be added to the list of financial transactions that could be taxed. The number seems quite plausible, because the do provide annual figures for the years up to 2008 (you can download an excel file here), when the total was €470 trillion. But they haven't been capable of producing numbers for annual turnover since. Someday, when I really have nothing to do, I guess I could download the 250 excel files for 2011 and work out what the total was.
Looks like my £1000 trillion number is massively underestimated. Just how many other operations like NYSE Liffe London are in action? And how much trading is simply going on without anyone having the foggiest clue about how much is involved?
(Note added 16th January : NYSE Liffe have excelled themselves! €2,667,602,732,639 in one day on the 13th January. Well done guys!! I'm sure it's all incredibly useful what you are doing!