For many years, it was believed that no correlation existed.
However, other studies have indicated that no such correlation exists.
Other economists doubt that a correlation between population reduction and economic growth exists.
We select a specific characteristic because a correlation exists between it and how the system is performing.
In fact, according to many studies, a positive correlation exists between environmental performance and economic performance.
No correlation exists between a team's success in spring training and its performance during the season.
For women, the same correlation existed, but it was weaker.
Just pointing out why the correlation might actually exist, that's all.
In the early 1990s, a direct correlation existed between the level of education and status.
It has long been known in education circles that a clear correlation exists between social class background and examination success.