In which decade did the numbers of catholic/jews first exceed the number of protestants?

I think you have it backwards. The Jews and Catholic Christians were around LONG before protestantism began.

http://en.wikipedia.org/wiki/Protestantism

http://en.wikipedia.org/wiki/Catholicism

http://en.wikipedia.org/wiki/Judaism

There were no Protestants at all prior to Luther's edicts on the church door.

Check this site.

http://www.britannica.com/eb/article-252534/ethics

To determine the decade when the numbers of Catholics and Jews first exceeded the number of Protestants, we would need to look at historical data and trends. Here's a step-by-step approach to finding this information:

1. Research reliable sources: Start by gathering historical data from reputable sources such as demographics reports, religious surveys, or academic studies. These may include national or regional census data, religious affiliation surveys, or historical archives.

2. Locate data sources: Look for sources that provide historical religious affiliation data categorized by specific time periods, such as decades. Government statistical agencies, research institutions, or religious organizations might have collected and published such data over the years.

3. Compare religious affiliation numbers: Once you have access to the relevant data, compare the numbers of Catholics, Jews, and Protestants for different decades. Look for a turning point where the combined numbers of Catholics and Jews exceeded the number of Protestants. This could involve analyzing trends, growth rates, or specific population milestones.

4. Assess accuracy and certainty: While analyzing the data, consider the accuracy and reliability of the sources you are using. Be aware of any potential biases or limitations in the data collection methods. Cross-reference multiple sources if possible to ensure the accuracy of your findings.

5. Determine the decade: Based on the data analysis, identify the decade when the numbers of Catholics and Jews first exceeded the number of Protestants. This will be the answer to your original question.

Remember, without further specific information, it is challenging to provide an exact answer to your question. The answer will depend on the particular country or region under consideration and the available historical data. Therefore, conducting thorough research using credible sources is crucial for obtaining accurate information.