 
   renderYearSelector: ->
     years = _.map [@state.currentYear..1900], (year) ->
-      option value: year, year
+      option value: year, key: year, year
     return select
       className: "input-date-year"
       value: @state.value.getFullYear()

    , months

  renderDaySelector: ->
    days = [1..daysInMonth(@state.value.getMonth() + 1, @state.value.getFullYear())]
    dayOptions = _.map days, (day) -> option value: day, day
    return select
      className: "input-date-day"
      value: @state.value.getDate()

    @props.onChange date

  renderMonthSelector: ->
    months = _.map monthMap, (month) -> option
      value: month[0], key: month[0]
    , month[1]

    return select
      className: "input-date-month"
      value: @state.value.getMonth()
