How often did trains change crews

I’ve been reading about the history of railroads and found it interesting how often trains would change crews, sometimes every 100 miles or so. It really shows the level of coordination and effort that went into railroad operations — does anyone have stories or specifics on crew changes from back in the day?

‌⁠‍⁠​‍​‍‌⁠‌​​‍​‍​⁠‍‍​‍​‍‌‍‌⁠‌⁠​‍‌⁠​‍‌‍‍‍​‍​‍​‍⁠​​‍​‍‌‍‍⁠​‍​‍​⁠‍‍​‍​‍‌‍⁠‍‌‍‌‌‌⁠‌⁠‌‌⁠⁠‌⁠‌​‌‍⁠⁠‌⁠​​‌‍‍‌‌‍​⁠​‍​‍​‍⁠​​‍​‍‌‍‍‌‌‍‌​​‍​‍​⁠‍‍​‍​‍‌‍⁠‍‌‍‌‌‌⁠‌⁠​‍​‍​‍⁠​​‍​‍‌‍‌​​‍​‍​⁠‍‍​‍​‍​⁠​‍​⁠​​​⁠​‍​⁠‌‍​⁠​​​⁠‌⁠​⁠​​​⁠‌‌​‍​‍​‍⁠​​‍​‍‌‍‍​​‍​‍​⁠‍‍​‍​‍‌⁠‌​‌‍‌⁠‌‌⁠⁠‌​‌‌‌​‍‍​‍⁠‌​⁠​⁠‌​​‍​⁠‍‌‌‌‌‌‌⁠‌​‌‍‌​‌‌‍​‌​⁠‌‌⁠‌⁠‌‌‌‍​‍​‍‌⁠⁠‌​