Many studies have found a strong association between the economic outcomes of nations and their performance on international cognitive tests. This association is often interpreted as evidence for the importance of cognitive skills for economic growth. However, several recent studies show that non-cognitive skills, such as test motivation, are also important for the performance on cognitive tests. This study disentangles the positive association between scores in achievement tests and economic growth into a cognitive and a non-cognitive component. We find that the effect of cognitive skills on economic growth reduces with roughly fifty percent when non-cognitive skills are taken into account. In our main specification, the estimated effects of cognitive and non-cognitive skills on economic growth are statistically significant and have the same size.