need a random number generator

i need to generate a random number between -0.5 and 0.5.

ive tried a solution on stack overflow by the user anthony pegram. i have modifyed it a bit ( i need the method to be called and used in a console.write line)

public static float nextfloat()
        {
            Random random = new Random();
            double val = random.NextDouble();
            val -= 0.5;

            return float.MaxValue * (float)val;
        }

by trying this i get numbers which are beyond -0.5 and 0.5 i get things like

1.7 1.005 etc