According to the oil company BP, in 2010, the United States used 19,148,000 barrels of oil a day, and worldwide around 87,382,000 barrels of oil per day were used.1 This includes oil used for (among other things) fuel and manufacturing.
If there were 309 million people in the United States in 2010, what was the daily consumption rate per capita (barrels per person) in the United States?

The daily consumption rate per capita is equal to USA daily consumption divided by the population in 2010.

This give us 0.062 barrels of oil (19,148,000/309,000,000).

Explanation:

The usage of barrels of oil is indicated in a daily total of 19,148,000 barrels.

The 2010 USA population is given as  309 million.

Therefore, to obtain the daily consumption of barrels of oil per person or the consumption rate per capita, the daily consumption is divided by the population.

Consumption rate per capita is the consumption per each head in the population.

This consumption rate per capita can be used to compare the consumption over time and with other countries with different population sizes.  This rate also indicates how each individual citizen of the USA is affected by the consumption of oil.

It does not actually imply that each individual has or can consume such quantity of oil per day.