Wondering what is the meaning of parameter leverage in AddFuture? I found following code in the documentation at https://www.quantconnect.com/docs/data-library/futures#Futures-Requesting-Futures-Data . What does the default value of 0m mean?

 

AddFuture(string symbol,          Resolution resolution = Resolution.Minute,          string market = null,          bool fillDataForward = true,          decimal leverage = 0m)