How many stars are within 100 light years of Earth. An estimated 14,600. This includes red dwarfs... Planets would need to be closer to red dwarfs to have life similar to ours... http://imagine.gsfc.nasa...tro/answers/980123d.html
Again a 133 stars within 50 light years are 'very similar' to our sun. Kepler surveyed less than 1% of space.