With a Price Change bar the price must change values to be counted as one count against the bar total count. So, a 10PC chart will display 10 changes of price, not 10 ticks. For example, if there were, in order, 3 trades at 9.25, 2 trades at 9.50, and then 7 trades at 9.25 again, then 3 price changes have occurred. Once the selected number of price changes are reached, the current bar is closed, and a new bar is created. I find this chart type gets rid of much noise in the price action.