Final answer:
The overall passage rate for initiatives from 1912 to 2014 cannot be determined based on the information provided.
Step-by-step explanation:
The overall passage rate for initiatives from 1912 to 2014 cannot be determined based on the information provided. The sources mentioned in the question do not specifically mention the passage rate for initiatives during that time period.
The term "passage rate for initiatives" typically refers to the success rate or likelihood of an initiative being approved or adopted. An initiative, in this context, is a proposal or plan for a specific action or project. The passage rate indicates the percentage of initiatives that are successfully implemented or accepted.