TickCounter provides information regarding the current number of ticks that are contained within the bar. The indicator can not only count starting from 0, but can also be set to count from a specified number down to 0. TickCounter can display the value either as absolute or as a percentage. It only works with candle charts in which the bars are established based on a fixed number of ticks.
When programming your own scripts, please use Bars, TicksCountForLastBar or Bars, LastBarCompleteness.