npm install vue-count-to

  <template>
    <countTo :startVal='startVal' :endVal='endVal' :duration='3000'></countTo>
  </template>

  <script>
    import countTo from 'vue-count-to';
    export default {
      components: { countTo },
      data () {
        return {
          startVal: 0,
          endVal: 2021
        }
      }
    }
  </script>

DEMO