How to calculate flash Density per sqkm per year from lat lon data

Hi there,

I have a data, which has locations on the map with lat and lon doubles. I can scatter plot them using m_map toolbox. I need to calculate their density variation over a certain lat lon limit. I want the legend in density(number) per sqkm per year (or month). I have one data file for one day. How do I go ahead ?

Any help would be highly appreciated.