# Load packages

# Core
library(tidyverse)
library(tidyquant)

Goal

Collect individual returns into a portfolio by assigning a weight to each stock

Choose your stocks.

from 2012-12-31 to 2017-12-31

1 Import stock prices

symbols <- c("MSFT", "NVDA", "JPM")

prices <- tq_get(x = symbols,
                 get = "stock.prices",
                 from = "2012-12-31",
                 to = "2017-12-31")

2 Convert prices to returns (quarterly)

asset_returns_tbl <- prices %>%

    group_by(symbol) %>%
    tq_transmute(select = adjusted,
                 mutate_fun = periodReturn,
                 period = "quarterly",
                 type = "log") %>%
    slice(-1) %>%
    ungroup() %>%
    
    set_names(c("asset", "date", "returns"))

3 Assign a weight to each asset (change the weigting scheme)

symbols <- asset_returns_tbl %>% distinct(asset) %>% pull()
symbols
## [1] "JPM"  "MSFT" "NVDA"
weights <- c(0.40, 0.30, 0.30)
weights
## [1] 0.4 0.3 0.3
w_tbl <- tibble(symbols, weights)
w_tbl 
## # A tibble: 3 × 2
##   symbols weights
##   <chr>     <dbl>
## 1 JPM         0.4
## 2 MSFT        0.3
## 3 NVDA        0.3

4 Build a portfolio

portfolio_returns_tbl <- asset_returns_tbl %>%
    
    tq_portfolio(assets_col   = asset,
                 returns_col  = returns,
                 weights      = w_tbl,
                 rebalance_on = "quarters")

portfolio_returns_tbl
## # A tibble: 20 × 2
##    date       portfolio.returns
##    <date>                 <dbl>
##  1 2013-03-28          0.0718  
##  2 2013-06-28          0.132   
##  3 2013-09-30          0.0178  
##  4 2013-12-31          0.100   
##  5 2014-03-31          0.0820  
##  6 2014-06-30          0.000629
##  7 2014-09-30          0.0541  
##  8 2014-12-31          0.0466  
##  9 2015-03-31         -0.0342  
## 10 2015-06-30          0.0635  
## 11 2015-09-30          0.0254  
## 12 2015-12-31          0.193   
## 13 2016-03-31         -0.0156  
## 14 2016-06-30          0.0853  
## 15 2016-09-30          0.182   
## 16 2016-12-30          0.265   
## 17 2017-03-31          0.0351  
## 18 2017-06-30          0.119   
## 19 2017-09-29          0.109   
## 20 2017-12-29          0.115

5 Plot: Portfolio Histogram and Density

Scatter plot

portfolio_returns_tbl %>%
    
    ggplot(mapping = aes(x = date, y = portfolio.returns)) +
    geom_point(color = "cornflowerblue") +
    
    # Formatting
    scale_x_date(date_breaks = "1 year",
                 date_labels = "%Y") +
    
    # Labeling
    labs(y = "quarterly returns",
         x = NULL,
         title = "Portfolio Returns Scatter")

Histogram

portfolio_returns_tbl %>%
    
    ggplot(mapping = aes(x = portfolio.returns)) +
    geom_histogram(fill = "cornflowerblue", binwidth = 0.005) +
    
    labs(x = "returns",
         title = "Portfolio Returns Distribution")

Histogram & Density Plot

portfolio_returns_tbl %>%
    
    ggplot(mapping = aes(x = portfolio.returns)) +
    geom_histogram(fill = "cornflowerblue", binwidth = 0.01) +
    geom_density() +
    
    # Formatting
    scale_x_continuous(labels = scales::percent_format())

     labs(x = "returns",
         y = "distribution",
         title = "Portfolio Histogram & Density")
## $x
## [1] "returns"
## 
## $y
## [1] "distribution"
## 
## $title
## [1] "Portfolio Histogram & Density"
## 
## attr(,"class")
## [1] "labels"

What return should you expect from the portfolio in a typical quarter?

In a typical quarter you can expect most times a return between 1% and 15%. This portfolio is fairly volatile, and it is possible to receive negative returns or returns higher than 20%.