47-55.1 Why does it seem more 1954 ADs survived

[vintovka]

Is i just me or does it seem more 54's are still around than other years? Did they make more? Been told 54 was first year that had plastic coated wires instead of cloth. Maybe this meant fewer 54 and 55-1 either burnt up or got junked due to electricl issues like mice chewing or shorts? Curious to know how many were actually made by year. My google-fu has failed so far.