What is the ratio of project managers to developers?

The ratio of project managers to developers can vary widely depending on several factors, including the nature of the project, team structure, and the specific roles of the individuals involved. 

In some tech environments, the ratio might be as high as 1:12 or even 1:20, particularly when dealing with well-established products where less hands-on management is needed. 

Marty Cagan of the Silicon Valley Product Group suggests a ratio of one product manager for every 6 to 10 developers. This aligns with the "seven, plus or minus two" principle, indicating that a team of 5 to 9 developers is ideal for effective management.

To sum up, it's essential to assess your organization's specific needs and project requirements to determine the most effective ratio.