old_contents: $(document).ready(function() {
    $('#plan-years').prop('disabled', true);
    $('#plans').prop('disabled', true);
  
    $('#carriers').change(function(e) {    
      $('#plans').prop('disabled', true);
      $('#plan-years').prop('disabled', false);
      var id = $('#carriers').val();
      $.getJSON('/carriers/'+ id +'/plan_years', function(data) {
        $.each(data, function(key, value) {
          $('#plan-years').append($('<option/>').attr("value", value).text(value));
        });
        get_carrier_plans();
        $("#plan-years").select2({dropdownCssClass: 'show-select-search'});
      });
    })
  
    $('#plan-years').change(function(e) {
      get_carrier_plans();
    });
  
    var get_carrier_plans = function() {
      var carrier_id = $('#carriers').val();
      var year = $('#plan-years').val();
      $('#plans').prop('disabled', false);
      $( "option[value|='']" ).remove();
      $(".btn[value='Calculate']").attr('class','btn btn-primary');
      $.getJSON('/carriers/'+ carrier_id +'/show_plans',{plan_year: year}, function(data) {
        $('#plans').empty();
        $.each(data, function(key, value) {
          $('#plans').append($('<option/>').attr("value", value._id).text(value.name).append(" : " + value.hios_plan_id));
        });
        if($('#plans').is(':empty')) {
          $('#plans').prop('disabled', true);
        }
        $("#plans").select2({dropdownCssClass: 'show-select-search'});
      });
    };
  
    $('#plans').change(function() {
      $(".btn[value='Calculate']").attr('class','btn btn-primary');
    });
  
    $('.date_picker').change(function() {
      $(".btn[value='Calculate']").attr('class','btn btn-primary');
    });
  
    $('.btn[value="Calculate"]').click(function() {
      $(this).attr('class','btn btn-default');
    });
  });
  
new_contents: $(document).ready(function() {
    $('#plan-years').prop('disabled', true);
    $('#plans').prop('disabled', true);
  
    $('#carriers').change(function(e) {    
      $('#plans').prop('disabled', true);
      $('#plan-years').prop('disabled', false);
      $('#plans').empty();
      $('#plan-years').empty();
      var id = $('#carriers').val();
      $.getJSON('/carriers/'+ id +'/plan_years', function(data) {
        $.each(data, function(key, value) {
          $('#plan-years').append($('<option/>').attr("value", value).text(value));
        });
        get_carrier_plans();
        $("#plan-years").select2({dropdownCssClass: 'show-select-search'});
      });
    })
  
    $('#plan-years').change(function(e) {
      get_carrier_plans();
    });
  
    var get_carrier_plans = function() {
      var carrier_id = $('#carriers').val();
      var year = $('#plan-years').val();
      $('#plans').prop('disabled', false);
      $( "option[value|='']" ).remove();
      $(".btn[value='Calculate']").attr('class','btn btn-primary');
      $.getJSON('/carriers/'+ carrier_id +'/show_plans',{plan_year: year}, function(data) {
        $('#plans').empty();
        $.each(data, function(key, value) {
          $('#plans').append($('<option/>').attr("value", value._id).text(value.name).append(" : " + value.hios_plan_id));
        });
        if($('#plans').is(':empty')) {
          $('#plans').prop('disabled', true);
        }
        $("#plans").select2({dropdownCssClass: 'show-select-search'});
      });
    };
  
    $('#plans').change(function() {
      $(".btn[value='Calculate']").attr('class','btn btn-primary');
    });
  
    $('.date_picker').change(function() {
      $(".btn[value='Calculate']").attr('class','btn btn-primary');
    });
  
    $('.btn[value="Calculate"]').click(function() {
      $(this).attr('class','btn btn-default');
    });
  });
  
subject: Fix for repeating years under premium calculator