Probabililty (of execution)  <probability> 

Number less than or equal to 1.0 (100%) and greater than 0.0 (0%) should be provided. A random number is generated which has an approximately uniform distribution, and with the probability provided, this handler will be invoked. When not invoked, the next handler defined with matching state/event will be evaluated. It is important to realize that this is a random distribution, and it will be realtively accurate over large samples, however in small samples there will be some variation from the provided probability.