anchor.diff:  %%------------------------------------------------------------------------------
   
   -record(rate_info, {
  -          average   :: 'wait' | concuerror_window_average:average(),
  +          average   :: concuerror_window_average:average(),
             prev      :: non_neg_integer(),
  -          ready     :: boolean(),
             timestamp :: timestamp()
            }).
   
  
positive.code: 
  init_rate_info() ->
    #rate_info{
       average   = wait,
       prev      = 0,
       ready     = false,
       timestamp = timestamp()
      }.
  
  
negative.code:     concuerror_estimator:estimate_completion(Estimation, TracesExplored, Rate),
    RateStr =
      case Rate of
        0    -> "  <1 /s";
        _    -> io_lib:format("~4w /s", [Rate])
      end,
    Str =
  