Stock Market - interpreting volume

I watch $UPVOL - $DWNVOL (NYSE, up-volume is trading volume for shares increasing in price, while down-volume is trading volume for shares decreasing in price.  $UPVOL minus $DWNVOL is the difference in trading volume.  On market-down days, the difference will be negative, while on market-up days, the difference will be positive).  I have watched it for a long time, but today I gained more insight.

What I realized:

• Constant slope means:
• - No rate of change, no acceleration, constant speed.
• - The rate of things changing is staying the same.
• The size of a bar
• - shows the amount of accelaration
• - or rate of change
• - continued acceleration down, changing slope down, shows panic
• Downward direction means:
• - The difference in the volume of stocks,  upVol vs dwnVol, is more down vol.
• A change in the direction (e.g., slope up instead of down) of the slope
• - shows a change in the sentiment