[anbu32]

The claim was that the crime rate was 50 times lower than today. 156/50 ~= 3.

[pdonis]

The crime rate, not the murder rate. Murder is only one crime.

[vacri]

How is "the crime rate" calculated?

[pdonis]

Um, the number of crimes in a given time period divided by the population?

[vacri]

So a murder is rated the same as stealing a penny candy?

[pdonis]

If you're just calculating the overall crime rate, yes. If you want to calculate the murder rate, the penny candy stealing rate, and other rates of individual crimes separately, of course you can do that too. (Though you might find it difficult to find numbers for penny candy stealing.)