DUBAI- Saudi Arabia's state oil giant Saudi Aramco plans to pay a base dividend of $75 billion in 2020, it said in a corporate overview posted to its website on Monday as it prepares for an initial public offering (IPO).

Aramco has been courting investors for the IPO, for which it seeks to achieve a $2 trillion valuation.

The document said the company would have "a progressive growing dividend on sustainable basis at board discretion".

The listing of Aramco, the world's largest oil company, is the centrepiece of Crown Prince Mohammed bin Salman's plan to shake up the Saudi economy and diversify away from oil. The IPO appears to be proceeding despite uncertainty over the timeline following a Sept. 14 attack on Aramco's facilities.

The document on Monday also mentioned the company's "progressive royalty scheme", with a marginal rate set at 15% up to $70 per barrel, 45% between $70 and $100, and 80% if the price rises higher.

(Writing by Nafisa Eltahir and Lisa Barrington; Editing by Kirsten Donovan and David Evans) ((lisa.barrington@thomsonreuters.com;))