for backtesting purposes what i need is the bid, the ask, and the "last" price for every second of every day for US stocks for the last 1 or 2 years. 2 years would be more than enough in my case. preferably in the form of a line chart, though i suppose a simple list of prices would be better than nothing. interactive brokers offer this for the last 6 months or so, but if i try to scroll back further than about 6 months (sometimes 7 months maximum) then all i get is a blank screen instead of a chart. it USED to be the case that i could scroll back in time as far as i liked, then suddenly one day sometime last year.. i went to bed, woke up the next morning to continue my backtesting effort, and just like that, the service had been discontinued, and that was the end of that. i have asked them about it again and again but nobody even knows what i am talking about, let alone how to help me. presumably someone in charge has simply decided to stop offering free historical tick by tick data for whatever reason, and that's that. please does anybody know where i can get this from? obviously free would be good, but i guess i would be willing to pay a fee if it came to it. thank you!