Aggregate FRED observations to a coarser frequency

Aggregates a long-format fred_tbl (with date, series_id, value) or a wide-format fred_tbl (date plus one column per series) to a coarser calendar frequency. For long format, aggregation is performed per series_id; for wide format, per numeric column.

Usage

fred_aggregate(data, fun = "mean", by = "month")

Arguments

data: A fred_tbl or data.frame with a date column.
fun: Character. Aggregation function. One of "mean", "sum", "first", "last", "median", "min", "max". Default "mean".
by: Character. Target frequency. One of "week", "month", "quarter", "year". Default "month".

Value

A fred_tbl with the same columns as the input, with date collapsed to period start.

Details

Use this when you have, say, daily Treasury yields and need a monthly average, or weekly initial claims aggregated to monthly totals. For server-side aggregation that mirrors FRED's own interpolation conventions, pass frequency = "m" to fred_series() instead.

Examples

# Synthetic example: aggregate daily synthetic data to monthly means
d <- seq(as.Date("2024-01-01"), as.Date("2024-06-30"), by = "day")
daily <- data.frame(date = d, series_id = "X", value = rnorm(length(d)))
fred_aggregate(daily, fun = "mean", by = "month")
#> # FRED: 6 rows
#>         date series_id       value
#> 1 2024-01-01         X -0.20970417
#> 2 2024-02-01         X  0.10408963
#> 3 2024-03-01         X  0.15213658
#> 4 2024-04-01         X  0.11632121
#> 5 2024-05-01         X  0.13332977
#> 6 2024-06-01         X -0.06317285

# Wide-format input also works
wide <- data.frame(date = d, A = rnorm(length(d)), B = rnorm(length(d)))
fred_aggregate(wide, fun = "sum", by = "quarter")
#> # FRED: 2 rows
#>         date          A         B
#> 1 2024-01-01 -0.8722382 -8.711310
#> 2 2024-04-01 25.8291942 -3.791956

# \donttest{
op <- options(fred.cache_dir = tempdir())
if (FALSE) { # \dontrun{
  daily_yields <- fred_series("DGS10", from = "2023-01-01")
  monthly_yields <- fred_aggregate(daily_yields, fun = "mean", by = "month")
} # }
options(op)
# }