So far in 2016, oil production and regulation tax revenues in Texas, the largest oil-producing state, are down 44% to $1.2 billion.

The continued retreat from low prices by oil and gas producers has helped ravage revenues in the sector. Among large-cap E&Ps, market losses reached $555 billion between third-quarter 2014 and fourth-quarter 2015.

But members of OPEC, which have left production open almost at full throttle, are seeing huge losses themselves.

OPEC oil export revenues, unadjusted for inflation, fell to about $404 billion in 2015, a 46% decline from the $753 billion earned in 2014, according to a report by the U.S. Energy Information Administration (EIA). The 2015 revenue total was the lowest amount earned by OPEC since 2004 export revenue totaled $295.1 billion (or $370.3 billion in 2015 dollars).

OPEC’s de facto leader and largest producer, Saudi Arabia, earned the largest share of export revenues with $130 billion in 2015. The kingdom’s share was one-third of total OPEC oil revenues.

However, Saudi Arabia’s revenue also lost the most in terms of value. The kingdom’s export revenues cratered by $116 billion, or 47%, from 2014.

Even less revenue could be in store for OPEC. The EIA estimates the cartel’s net oil export revenues could fall to $341 billion in 2016—another 16% drop—based on projections of global oil prices and OPEC production levels.

EIA’s June Short-Term Energy Outlook estimates production will rise 800,000 barrels per day (Mbbl/d) to 32.4 MMbbl/d in 2016.

Including Iran, the median export revenue loss for OPEC nations was $24.3 billion last year. On a per capita basis, OPEC countries’ net oil export earnings are expected to deteriorate by about 17% in 2016.

Darren Barbee can be reached at dbarbee@hartenergy.com.