library(fpp2)
## Loading required package: ggplot2
## Loading required package: forecast
## Loading required package: fma
## Loading required package: expsmooth
library(seasonal)
Plastic sales tend to peak in the middle of the month. ### b
### c The decomposition shows the same monthly trend as well as a general upward tick in production (excluding the last month). ### d
## Warning: Removed 12 rows containing missing values (geom_path).
### e
## Warning: Removed 12 rows containing missing values (geom_path).
The outlier effects the seasonally adjusted value greatly, but does not greatly effect the trend line. ### f
## Warning: Removed 12 rows containing missing values (geom_path).
The later in the data the outlier is, the less it effects the trend line. ## Problem 6.3 ### Load Data
## readxl works best with a newer version of the tibble package.
## You currently have tibble v1.4.2.
## Falling back to column name repair from tibble <= v1.4.2.
## Message displays once per session.
As expected, the biggest outlier to air traffic was 2001. Additionally, there has been recent volatility perhaps due to fluctuating oil prices and other travel-related concerns.