Ecopetrol S.A., HollyFrontier Corp, Cabot Oil & Gas Corp had the highest volumes yesterday.

A quick recap of where the last trading session ended: Markets completed a mixed session yesterday, as after dropping 0.29%, Nasdaq closed at 12,037. Dow Jones gained 0.2% and closed at 33,875.

Why trading volume matters?

Trading volume is simply the total number of shares traded including both buy and sell orders. If a stock has appreciated on high volume, it is more likely to be a sustained move compared to an appreciation with low volume. Typically, high volume trading sessions are considered significant occurrences and closely watched by traders.

While trading was mostly sideways yesterday, several energy stocks were actively traded. Here's an update:

Ecopetrol | 247% higher than rolling average

Colombia's largest petroleum supplier is now trading 36.46% below the significant high of $17.47 it set around 10 months ago. The stock has been trending positively for about a month. Ecopetrol's market cap is currently $23.87 billion with an average daily volume of 1.95 million shares.

Yesterday's trading volume peaked at 4.83 million shares, thereby blitzing the daily average of 1.95 million by 247%.

Ecopetrol | 247% higher than rolling average

Yesterday's trading volume peaked at 4.83 million shares, thereby blitzing the daily average of 1.95 million by 247%.

Ecopetrol | 247% higher than rolling average

Yesterday's trading volume peaked at 4.83 million shares, thereby blitzing the daily average of 1.95 million by 247%.

— Average trading volume refers to a 21-day rolling average.