Tick Chart

A tick chart forms a new bar after a fixed number of price updates rather than after a fixed amount of time. Bars therefore appear quickly when quotes are arriving fast and slowly when the market is quiet, so the horizontal axis measures activity instead of the clock. The four values inside each bar are recorded exactly as they are on a time chart; only the rule that ends a bar is different. In spot forex the thing being counted is the platform's own count of quote updates, not a count of executed trades, because there is no central record of transacted size. Two providers drawing on different sets of price sources will therefore end their bars at different moments and draw different charts of the same market, and a tick chart's bar count cannot be compared across platforms. The count itself is a setting rather than a property of the market, which means — as with any chart type built on a chosen threshold — that changing it changes every bar on screen.