"..."Bear" flag in a downtrend. After a big rout, the flag seemingly presents a chance to re-group before continuing in the same direction (down.) diminishes during the pause and then rapidly expands on the continuation..."(http://www.chartpatterns.com/flagandpennantcharts.htm)
"...The height of the flagpole may be subtracted from the breakout area at the end of the flag to determine the expected decline which follows. This is why the pattern is often found in the middle of stock declines..." (https://thestockbandit.com/bear-flag/)
Let me know in the comments what you think?