The federal government's March Resources and Energy Quarterly stated the value of Australia's metallurgical coal exports reached a record high for a second consecutive year in 2018-19.

Export earnings increased to $44 billion in real terms, driven by high prices and, to a lesser extent, growing export volumes.

Metallurgical coal export earnings are projected to decline in real terms to $35 billion in 2021-22, as prices ease, before recovering to $38 billion in 2024-25.

Export volumes are projected to grow solidly over the next five years, increasing from 184 million tonnes in 2018-19 to 205 million tonnes in 2024-25.

Higher export volumes will be driven by the ramp up of production at a number of mines, the largest of which is Qcoal's 10 million tonne per annum Byerwen mine in the Bowen Basin in Queensland.

The closure of a number of mines due to resource depletion is expected to weigh on export volumes towards the end of the next five years.

"The collapse of a roof at Anglo American's Moranbah North mine in Queensland in late January 2020 will weigh on production in the short term," the report states.

"Anglo American has revised down its metallurgical coal production guidance to 19-21 million tonnes for 2020 as a result of the accident, after producing 23 million tonnes last year."