如果每年固定撥出一定比例的薪水，拿來存款投資，考量薪資成長率的情況下總共會有多少資金？

每年拿薪水固定比例的投資報酬.ipynb

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  "metadata": {
    "colab": {
      "provenance": [],
      "name": "每年拿薪水固定比例的投資報酬.ipynb",
      "authorship_tag": "ABX9TyObVopdsDmSmjhyNv5own3i",
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      "name": "python3",
      "display_name": "Python 3"
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    "language_info": {
      "name": "python"
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  "cells": [
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "view-in-github",
        "colab_type": "text"
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      "source": [
        "<a href=\"https://colab.research.google.com/gist/davidhcefx/f2a8df24aed327ea4602fe0ce51907d5/.ipynb\" target=\"_parent\"><img src=\"https://colab.research.google.com/assets/colab-badge.svg\" alt=\"Open In Colab\"/></a>"
      ]
    },
    {
      "cell_type": "markdown",
      "source": [
        "# 每年拿薪水固定比例\n",
        "\n",
        "如果每年固定撥出一定比例的薪水，拿來存款投資，考量薪資成長率的情況下總共會有多少資金？"
      ],
      "metadata": {
        "id": "hf3Z-zqstk2F"
      }
    },
    {
      "cell_type": "code",
      "source": [
        "# 工作年數\n",
        "WORK_YEARS = 40\n",
        "# 第一年年收入\n",
        "INIT_INCOME = 480000\n",
        "# 薪資成長率 (年)\n",
        "GROWTH = '3%'\n",
        "# 投資佔收入比例\n",
        "DEP_RATIO = '15%'\n",
        "# 投資的平均年化報酬率\n",
        "ROI = '5%'\n",
        "\n",
        "\n",
        "def parse_percentage(s: str) -> float:\n",
        "    if not isinstance(s, str) or not s.endswith('%'):\n",
        "        raise TypeError('Wrong format')\n",
        "    return float(s[:-1]) / 100\n",
        "\n",
        "\n",
        "def calc_return() -> int:\n",
        "    ret = 0\n",
        "    work_years = WORK_YEARS\n",
        "    init_income = INIT_INCOME\n",
        "    growth = parse_percentage(GROWTH)\n",
        "    dep_ratio = parse_percentage(DEP_RATIO)\n",
        "    roi = parse_percentage(ROI)\n",
        "    incomes = [init_income] * work_years  # income per year\n",
        "    for i in range(1, work_years):\n",
        "        incomes[i] = incomes[i-1] * (1 + growth)\n",
        "    deposites = [ic * dep_ratio for ic in incomes]\n",
        "    for i in range(work_years):\n",
        "        ret += deposites[work_years - 1 - i] * (1 + roi) ** i\n",
        "\n",
        "    return int(ret)\n",
        "\n",
        "r = calc_return()\n",
        "print('Total return:', r)\n",
        "print('總資金: {} 萬'.format(r / 10000))"
      ],
      "metadata": {
        "colab": {
          "base_uri": "https://localhost:8080/"
        },
        "id": "L0drMEbTpVhQ",
        "outputId": "4170227a-d094-4872-c310-da9b9c3617f6"
      },
      "execution_count": 1,
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "Total return: 13600623\n",
            "總資金: 1360.0623 萬\n"
          ]
        }
      ]
    }
  ]
}