Net revenue for members of the Organization of Petroleum Exporting Countries from oil dropped nearly 50 percent year-on-year, U.S. analysis found.

Crude oil prices began their descent from $100 per barrel in 2014 as the increase in U.S. crude oil production helped push markets heavily toward the supply side. Output for members of OPEC remains robust, however, as ministers there said they expect a rebound in demand in the latter quarters of 2016.

A report from the U.S. Energy Information Administration found oil export revenue for OPEC members in 2015 was a collective $404 billion, 46 percent lower than the previous year.

"OPEC members' 2015 net oil export revenue was at the lowest level since 2004, with significant implications for the fiscal condition of member countries that rely heavily on oil sales to fund social programs and to import other goods and services," EIA's report read.

Saudi Arabia, the de facto head of OPEC, unveiled an economic agenda dubbed Vision 2030, which aims to boost the country's non-oil revenue and generate revenue through the public listing of shares in the Saudi Arabian Oil Co., known also as Saudi Aramco. Billed as the largest-ever IPO, the 2018 offering would likely value the company at $2 trillion. According to Moody's Investors Service, however, the Saudi economy will grow at an average rate of 2 percent, compared with the 5 percent growth rate in the four years ending in 2015.

EIA said unplanned outages in countries like Libya and Nigeria are adding insult to injury. In Venezuela, further declines are expected because of work stoppages in response to a lack of payment from the state-owned Petroleos de Venezuela. Most of the OPEC members in the Persian Gulf region are impacted less than their peers, the report found.

In terms of a potential societal impact, EIA found that, when adjusted for inflation, net OPEC oil revenue was around $606 per person last year, down more than 80 percent from 1980.