Mark's Gospel Was Written Sometime in the Mid-Fifties, Say, Around the Year a D 55

Mark was peter's traveling companion until the fifties. If he had to have written before luke was published in 59, then that would mean mark must have written his gospel some time in that decade. We can therefore estimate that mark's gospel was written sometime in the mid fifties,. say, around the year a d 55. And what about the gospel of matthew? The evidence suggests that matthew was written after mark and you can see the evidence for that on my page on the synoptic gospel.