How come most forex data providers that provide you with tick data do not also provide you with the bid and ask volume? IQFeed is one that does, but most others dont afaik.

forex trading is decentralized, there is no NBBO like in US stocks. so the bid-ask is set by the broker dealer, not by actual market participants. the volume you're seeing is only the volume your broker provides, based on the retail traders using that broker. so its basically useless, because that is such an insignificant number compared to the size of the overall market.

djporter91 

forex trading is decentralized, there is no NBBO like in US stocks. so the bid-ask is set by the broker dealer, not by actual market participants. the volume you're seeing is only the volume your broker provides, based on the retail traders using that broker. so its basically useless, because that is such an insignificant number compared to the size of the overall market.

FXCM says their 'real volume' is quite meaningful because they capture 1% of the market.

Also, it's said that tick volume can be a good proxy for real volume. I can see how this would be true unless all smart money is traded OTC.