I think one thing needs to be stated; I do not have concrete numbers, but it seems as if algorithmic trading technology has actually levelled the playing field

I think one thing needs to be stated; I do not have concrete numbers, but it seems as if algorithmic trading technology has actually levelled the playing field and created more jobs. I am a series 3 (commodities) and quant. Take this example, at one point in time people were literally trading seats on the exchange, and a seat on the NYSE was as high as 3 million !!! While there may have been more people with those jobs than today, you had virtually no choice to be in a large institution. Today, almost anyone can raise some money, use the simple Interactive Brokers API which sits on top of FIX protocol, and build a trading strategy. The main reason I think you don't see more competition from small new firms - even though there is a lot - is that the regulation is fierce and most funds already offer nice compensation. Within those firms, yes there may be some decline in those jobs like a floor trader, but someone has to program and manage those algorithms. It's also important to keep in mind that many firms are only replacing execution traders while directing traders through fundamental analysis, and if all firms ever go completely algorithmic you'll find firms trying to exploit these algos in ways unique to humans.