Plot calendar-based development statistics

Visualise an object of class Calendar as a time-series plot. The selected metric is plotted over the calendar-style calendar_var, or over the calendar development variable stored in attr(x, "dev_var").

Ratio metrics (lr, clr) and proportion metrics (loss_prop, rp_prop, closs_prop, crp_prop) are plotted on the original scale and displayed as percentages via y-axis labels. Amount metrics (loss, rp, margin, closs, crp, cmargin) are plotted on the original scale and displayed using y-axis labels scaled by amount_divisor.

If grouping variables are present, lines are drawn separately by group.

Usage

# S3 method for class 'Calendar'
plot(
  x,
  value_var = "clr",
  x_by = c("period", "dev"),
  amount_divisor = 1e+08,
  theme = c("view", "save", "shiny"),
  ...
)

Arguments

x

An object of class Calendar.

value_var

A single metric to plot. Must be one of: "lr", "clr", "loss", "rp", "margin", "closs", "crp", "cmargin", "loss_prop", "rp_prop", "closs_prop", or "crp_prop".

x_by

X-axis basis. One of:

"period"

Use the calendar variable stored in attr(x, "calendar_var").

"dev"

Use the sequential dev column.

amount_divisor

Numeric scaling factor used only for y-axis labels of amount variables. Default is 1e8.

theme

A string passed to .switch_theme() ("view", "save", "shiny").

...

Additional arguments passed to .switch_theme().

Value

A ggplot object.

Details

The x-axis uses either the calendar variable stored in attr(x, "calendar_var") or the sequential dev column, depending on x_by.

The loss ratio is defined as: $$lr = loss / rp$$

where rp denotes risk premium rather than written premium.

Examples

if (FALSE) { # \dontrun{
x <- build_calendar(df, cv_nm, cym)

plot(x)
plot(x, value_var = "lr")
plot(x, x_by = "dev")
} # }