[get_ntd()] downloads Excel file with the adjusted or raw monthly ridership files provided by the National Transit Database and transforms the data into a long-format data frame with one or more variable. Optionally cache the source spreadsheet or filter by agency or mode.
Usage
get_ntd(
agency = "all",
data_type = "adjusted",
ntd_variable = "UPT",
modes = "all",
cache = getOption("ntdr.cache", FALSE)
)Arguments
- agency
Name of the transit agency to retrieve. Defaults to `all` agencies
- data_type
Type of NTD data. Either "raw" for data released without adjustments or "adjusted" for data with adjustments and estimates
- ntd_variable
Which variable or variables to return. `UPT` for unlinked passenger trips, `VRM` for vehicle revenue miles, `VRH` for vehicle revenue hours, or `VOMS` for vehicles operated in maximum service.
- modes
Transit mode or modes to retrieve. Common modes include `MB` (bus), `CR` (commuter rail), `HR` (heavy rail), `LR` (light rail). Defaults to `all` modes.
- cache
Cache downloaded data. Defaults to `FALSE`. Set a default value with the "ntdr.cache" option.
Examples
if (FALSE) { # interactive()
get_ntd(agency = "City of Madison", modes = c("MB", "DR"))
}