You may have good metrics on the number of incidents that were pre-dated with announcements, but you probably have very bad metrics on the number of announcements that were followed by incidents.
There's no way you can make a statement about how strong the link is without that information.
There's an important point that should be made here.
http://en.wikipedia.org/wiki/Confirmation_bias#Biased_search...
You may have good metrics on the number of incidents that were pre-dated with announcements, but you probably have very bad metrics on the number of announcements that were followed by incidents.
There's no way you can make a statement about how strong the link is without that information.