Basic Vue-based loan calculator

mortage.vue

<template>
  <div id="app-container">
  <form>
    <label for="principal">Principal</label>
    <input type="number" name="principal" v-model="principal" />
    <label for="rate">Rate</label>
    <input type="text" name="rate" v-model="rate" />
  </form>
  <p>
    Total Amount: {{totalAmount}}
  </p>
  <p>
    Payments:
  </p>
</div>
</template>

<script>
export default {
  name: 'app',
  data () {
    rate: 0.05,
    principal: 20000,
    time: 5,
    increments: 12

  },
  computed: {
    totalAmount: function() {
      // Calculate compound interest using the formula: P (1 + r/n) (nt) - P
      return Math.floor(this.principal * Math.pow((1 + this.rate / this.increments), this.increments * this.time));
    }
  }
}
</script>

Here's an example of this working with slightly altered code.
https://jsfiddle.net/baconchez/1pm7qez9/