Early 90's movie, cant remember what its called?

Was a futureistic type of movie. There was a man who went back in
time to visit all sorts of devestating events; I believe he wore a
trenchcoat. One point in the movie, he is flipping his coin and it
falls; a news woman hears it which sets off a chain of events because
she was suppose to die.

Early 90's movie I believe