rates: Change rates and contributions

In hicp: Harmonised Index of Consumer Prices

Change rates and contributions

Description

Function rates() derives monthly, quarterly and annual rates of change from an index series.

Function contrib() computes the contributions of a subcomponent (e.g., food, energy) to the change rate of the overall index (for chained indices with price reference period December of the previous year).

Usage

rates(x, t, type="year", settings=list())

contrib(x, w, t, x.all, w.all, type="year", settings=list())

Arguments

x, x.all	numeric vector of index values of the subcomponent (x) and the overall index (x.all).
w, w.all	numeric vector of weights of the subcomponent (w) and the overall index (w.all).
t	date vector in format YYYY-MM-DD with monthly frequency, that is, one observation per month. Quarterly and yearly frequencies are also supported.
type	character specifying the type of change rate. Allowed values are month for monthly change rates, quarter for quarterly change rates, and year for annual change rates. See also details.
settings	list of control settings to be used. The following settings are supported: chatty : logical indicating if package-specific warnings and info messages should be printed or not. The default is getOption("hicp.chatty"). freq : character specifying the frequency of t. Allowed values are month, quarter, year, and auto (the default). For auto, the frequency is internally derived from t. method : character specifying the method for decomposing the change rates. Allowed values are ribe (the default) and kirchner.

Details

For monthly frequency, the change rates show the percentage change of x in the current month compared to the previous month (monthly change rates, m-1), compared to three months ago (quarterly change rates, m-3), or compared to the same month one year before (annual change rates, m-12).

For quarterly frequency, the change rates show the percentage change of x in the current quarter compared to the previous quarter (quarterly change rates, q-1) or compared to the same quarter one year before (annual change rates, q-4).

For yearly frequency, the change rates show the percentage change of x in the current year compared to the previous year (annual change rates, y-1). If x is an annual index produced by convert(), the annual change rates correspond to annual average change rates.

Value

A numeric vector of the same length as x.

Author(s)

Sebastian Weinand

References

European Commission, Eurostat, Harmonised Index of Consumer Prices (HICP) - Methodological Manual - 2024 edition, Publications Office of the European Union, 2024, https://data.europa.eu/doi/10.2785/055028.

Examples

### EXAMPLE 1

p <- rnorm(n=37,mean=100,sd=5)
t <- seq.Date(from=as.Date("2020-12-01"), by="1 month", length.out=length(p))

# compute change rates:
rates(x=p, t=t, type="month") # one month to the previous month
rates(x=p, t=t, type="year")  # month to the same month of previous year

# compute annual average rate of change:
pa <- convert(x=p, t=t, type="y") # now annual frequency
rates(x=pa, t=as.Date(names(pa)), type="year")

# compute 12-month average rate of change:
pmvg <- convert(x=p, t=t, type="12mavg") # still monthly frequency
rates(x=pmvg, t=t, type="year")

### EXAMPLE 2: Ribe contributions using published HICP data

library(data.table)
library(restatapi)
options(restatapi_cores=1)  # set cores for testing on CRAN
options(hicp.chatty=FALSE)  # suppress package messages and warnings

# import monthly price indices:
prc <- hicp::data(id="prc_hicp_midx", filter=list(unit="I15", geo="EA"))
prc[, "time":=as.Date(paste0(time, "-01"))]
prc[, "year":=as.integer(format(time, "%Y"))]
setnames(x=prc, old="values", new="index")

# import item weights:
inw <- hicp::data(id="prc_hicp_inw", filter=list(geo="EA"))
inw[, "time":=as.integer(time)]
setnames(x=inw, old=c("time","values"), new=c("year","weight"))

# merge price indices and item weights:
hicp.data <- merge(x=prc, y=inw, by=c("geo","coicop","year"), all.x=TRUE)

# add all-items hicp:
hicp.data <- merge(x=hicp.data,
                   y=hicp.data[coicop=="CP00", list(geo,time,index,weight)],
                   by=c("geo","time"), all.x=TRUE, suffixes=c("","_all"))

# ribe decomposition:
hicp.data[, "ribe" := contrib(x=index, w=weight, t=time, 
                              x.all=index_all, w.all=weight_all,
                              type="year", settings=list(method="ribe")), by="coicop"]

# plot annual change rates over time:
plot(rates(x=index, t=time, type="year")~time,
     data=hicp.data[coicop=="CP00",],
     type="l", ylim=c(-2,12))

# add contribution of energy to plot:
lines(ribe~time, data=hicp.data[coicop=="NRG"], col="red")

hicp documentation built on Aug. 8, 2025, 6:30 p.m.