stock_investment.sc

// based on https://github.com/pheymann/investment-library
// to execute follow: https://github.com/pheymann/investment-library#how-to-install-and-use-it-with-a-docker-based-setup

/* Result: 50,000 EUR capital and 40 years runtime (ignoring dividends for now)
 *   - lump sum investment at the beginning leads to: 274383.125EUR
 *   - continues investment over 40 years leads to: 130788.584EUR
 *   - spread investment over the first 5 years leads to: 250692.769EUR
 *
 * Assumption: flat 25% capital gains tax.
 */

import $ivy.`com.github.pheymann::investment-library:0.0.0`
import investment._, units._, distributions._

// this stock's value growth 5% annually
  val valueGrowth: ReturnDistribution[Year] = year => {
    Percentage.fromInt(5)
  }

// this stock pays 1% dividends annually
val dividends: ReturnDistribution[Year] = year => {
  Percentage.fromInt(1)
}

// lumpsum investment of 50,000EUR
{
  val orderFlow: OrderDistribution[Year] = (year, balance) => {
    // sell all after 40 years
    if (year == Year(40)) {
      balance.addOrder(Order.Liquidation)
    }
    // lump sum at the beginning
    else if (year == Year(0)) {
      balance.addOrder(Order.Purchase(Capital(50000)))
    }
    else {
      balance
    }
  }

  // invest for 10 years with an initial stock share price of 1.
  val result = stocks.invest(
    investmentLifetime    = Years.forYears(40),
    initialSharePrice     = Capital(1),
    orderDist             = orderFlow,
    valueGrowthReturnDist = valueGrowth,
    dividendDist          = dividends,
    taxation              = Taxation.fifoBasedTaxation(capitalGainsTax = Percentage.fromInt(25))
  )

    println("##### Lumpsum investment of 50,000EUR")
  println(prettyPrint(result))
}

// continues investment of 50,000EUR
{
  val orderFlow: OrderDistribution[Year] = (year, balance) => {
    // sell all after 40 years
    if (year == Year(40)) {
      balance.addOrder(Order.Liquidation)
    }
    else {
      balance.addOrder(Order.Purchase(Capital.fromDouble(50000/40)))
    }
  }

  // invest for 10 years with an initial stock share price of 1.
  val result = stocks.invest(
    investmentLifetime    = Years.forYears(40),
    initialSharePrice     = Capital(1),
    orderDist             = orderFlow,
    valueGrowthReturnDist = valueGrowth,
    dividendDist          = dividends,
    taxation              = Taxation.fifoBasedTaxation(capitalGainsTax = Percentage.fromInt(25))
  )

  println("\n\n##### Cont inues investment of 50,000EUR")
  println(prettyPrint(result))
}

// Spread investment of 50,000EUR
{
  val orderFlow: OrderDistribution[Year] = (year, balance) => {
    // sell all after 40 years
    if (year == Year(40)) {
      balance.addOrder(Order.Liquidation)
    }    
    else if (year >= Year(0) && year <= Year(4)) {
      balance.addOrder(Order.Purchase(Capital.fromDouble(50000/5)))
    }
    else {
      balance
    }
  }

  // invest for 40 years with an initial stock share price of 1.
  val result = stocks.invest(
    investmentLifetime    = Years.forYears(40),
    initialSharePrice     = Capital(1),
    orderDist             = orderFlow,
    valueGrowthReturnDist = valueGrowth,
    dividendDist          = dividends,
    taxation              = Taxation.fifoBasedTaxation(capitalGainsTax = Percentage.fromInt(25))
  )

  println("\n\n##### Spread investment of 50,000EUR")
  println(prettyPrint(result))
}