Two studies by Key Perspectives Ltd, surveying researchers at universities worldwide, have shown the same result. This result has also been found in surveys carried out in individual countries by other surveyors.
When researchers are asked the question, “if your employer or funder required you to make your work Open Access, how would you respond?” the result is shown in the graph below.

This result is borne out in practice. Those universities and funders with mandatory Open Access policies are quickly accumulating content. The oldest mandate, that introduced in 2003 at the School of Electronics & Computer Science at the University of Southampton, has resulted in over 90% compliance and the School’s repository has almost 12000 items in it.
The intentions of researchers are also shown below, broken down by geographical region.
Original studies
Key Perspectives Ltd (2005): Open Access self-archiving: an author study: click here
Arthur Sale (2006): Comparison of IR content policies in Australia: click here