With so many stocks on consistent decline, how is this so with only a fraction of percent of shares outstanding transacted each day?

The vast majority of stocks are on consistent decline over an extended period, with little change to the fundamentals of the company. Yet the volume traded each day seems to be a very small percentage, even a fraction of a percentage of the total shares outstanding. It appears that the market pricing mechanism does not account for the 99% (or so) of share owners that don’t engage in selling of the security. With little to no volume, how does this devalue the share price, when this type of market activity would indicate little to no selling? Sure, this would also indicate no increased buying, however the shares are already ‘bought’ and accounted for, so how would this result in negative price action? These questions are asked generally because it is clearly happening across the market. Though, as an example, I will toss out Coca Cola: 4.3B shares outstanding, 13M avg. daily volume = fraction % of shares outstanding traded daily, down almost 6% past 3 months. This is just a snapshot example, again, its clearly happening across the market. Trying to understand what mechanisms drive this price action, and an explanation as to the logic behind said mechanism.