The form of the MSC has also changed markedly over the years. It was originally conceived as a means by which readers could test themselves on the Culbertson System, and for years it was held that there was only one correct answer to each problem – there being only one correct answer in the context of the Culbertson System. In the 1940s a system of partial credits was instituted, with the "correct" answer receiving 100 points and lesser awards going to other answers. This approach continues in 2009.