Based on Launchpad's claim that he's crash 4,298 times since Scrooge disappeared 40 years ago, that means that he has crashed about 107.5 times per year. Or, roughly once every three days for 40 full years.
When Magica and Scrooge travel to the past, they visit the Roman Empire (ca. 100), Custer's Last Stand at the Battle of Little Bighorn (1876), and the Hindenburg Disaster (1937).