cleansing up bad ticks (any time you see a foul tick chances are you'll try out forcing backfill in hope that data seller has cleaned up its database and you will get preset data - operates well for eSignal that actually seems to fix negative ticks when they occur) https://amibroker-data-feed19630.blogstival.com/50458931/the-5-second-trick-for-amibroker-data