QUARTERLY Statement
- QUARTERLY options;
The QUARTERLY statement must be used when the
input data are quarterly time series.
This statement includes options that determine the
computations performed by the
procedure and what is in the printed output.
The DATE= option or the START= option must be used.
The following options can appear in the QUARTERLY
statement.
- ADDITIVE
-
performs additive adjustments.
If this option is omitted, the procedure
performs multiplicative adjustments.
- CHARTS= STANDARD
- CHARTS= FULL
- CHARTS= NONE
-
specifies the charts to be produced by the procedure.
The default value is CHARTS=STANDARD,
which specifies four quarterly seasonal charts
and a trend cycle chart. If you specify
CHARTS=FULL (or CHARTS=ALL), the procedure prints
additional charts of irregular and seasonal factors.
To print no charts, specify CHARTS=NONE.
The TABLES statement can also be used to specify
particular charts to be printed. The presence of a
TABLES statement overrides the default value of
CHARTS=STANDARD, that is, if a TABLES statement
is specified, and no CHARTS=option is specified,
no charts (nor tables) are printed except those
given in the TABLES statement.
However, if both the CHARTS= option and a TABLES
statement are given, the charts corresponding to
the CHARTS= option and those requested by the TABLES
statement are printed.
For example, suppose you only wanted charts G1, the final
seasonally adjusted series and trend cycle, and G4,
the final irregular and final modified irregular series.
This is accomplished by specifying the following statements.
quarterly date=date;
tables g1 g4;
- DATE= variable
-
specifies a variable that gives the date for each observation.
The starting and ending dates are obtained from the first and
last values of the DATE= variable, which must contain SAS date
values. The procedure checks values of the DATE= variable
to ensure that the input observations are sequenced correctly.
This variable is automatically added to the OUTPUT= data set
if one is requested, and extrapolated if necessary.
If the DATE= option is not specified, the
START= option must be specified.
The DATE= option and the START= and END= options can be used in
combination to subset a series for processing.
For example, suppose you have a series with 10 years
of quarterly data (40 observations, no missing values)
beginning in '1970Q1' and ending in '1979Q4',
and you only want to seasonally adjust four years
beginning in 1974Q1 and ending in 1977Q4. Specifying
quarterly date=variable start='1974q1' end='1977q4';
seasonally adjusts only this
subset of the data. If, instead, you wanted to
adjust the last six years of data, only the
START= is needed:
quarterly date=variable start='1974q1';
- END= `yyyyQq'
-
specifies that only the part of the input series
ending with the quarter and year given be adjusted
(for example, END='1973Q4').
The specification must be enclosed in quotes
and q must be 1, 2, 3, or 4.
See the DATE= variable option for using the
START= and END= options to subset a series.
- FULLWEIGHT= value
-
assigns weights to irregular values based on
their distance from the mean in standard
deviation units. The weights are used for
estimating seasonal and trend cycle components.
Irregular values less than the FULLWEIGHT= value
(in standard deviation units) are assigned full
weights of 1, values that fall between the
ZEROWEIGHT= and FULLWEIGHT= limits are assigned
weights linearly graduated between 0 and 1, and
values greater than the ZEROWEIGHT= limit are
assigned a weight of 0.
For example, if ZEROWEIGHT=2 and FULLWEIGHT=1,
a value 1.3 standard deviations from the
mean would be assigned a graduated weight.
The default is FULLWEIGHT=1.5.
- NDEC= n
-
specifies the number of decimal places shown on the output tables.
This option has no effect on the precision of the
variables in the output data set.
- PRINTOUT= STANDARD
- PRINTOUT= LONG
- PRINTOUT= FULL
- PRINTOUT= NONE
-
specifies the tables to print.
If PRINTOUT=STANDARD is specified, between 17 and 27
tables are printed, depending on the other options
that are specified. PRINTOUT=LONG prints between 27
and 39 tables, and PRINTOUT=FULL prints between
44 and 59 tables. Specifying PRINTOUT=NONE results
in no tables being printed.
The default is PRINTOUT=STANDARD.
The TABLES statement can also specify
particular quarterly tables to be printed.
If no PRINTOUT= is given, and a TABLES statement
is given, the TABLES statement overrides the default
value of PRINTOUT=STANDARD; that is, no tables (or charts)
are printed except those given in the TABLES statement.
However, if both the PRINTOUT= option and a TABLES
statement are given, the tables corresponding to
the PRINTOUT= option and those requested by the
TABLES statement are printed.
- START= 'yyyyQq'
-
adjusts only the part of the input series
starting with the quarter and year given.
When the DATE= option is not used, the START= option
gives the year and quarter of the first input observation
(for example, START='1967Q1').
The specification must be enclosed in quotes,
and q must be 1, 2, 3, or 4.
START= must be specified if the DATE= option is not given.
If START= is specified (and no DATE= is given),
and an OUTPUT= data set is requested,
a variable named _DATE_ is added to the
data set, giving the date value for a given
observation. See the DATE= option for using
the START= and END= options to subset a series.
- SUMMARY
-
specifies that the input is already seasonally
adjusted and that the procedure is to produce
summary measures. If this option is omitted,
the procedure performs seasonal adjustment of
the input data before calculating summary measures.
- TRENDADJ
-
modifies extreme irregular values prior to computing the trend
cycle estimates. If this option is omitted, the trend cycle is
computed without modification for extremes.
- ZEROWEIGHT= value
-
assigns weights to irregular
values based on their distance from the mean
in standard deviation units. The weights are
used for estimating seasonal and trend cycle
components. Irregular values beyond the standard
deviation limit specified in the ZEROWEIGHT= option are
assigned zero weights. Values that fall between
the two limits (ZEROWEIGHT= and FULLWEIGHT=)
are assigned weights linearly graduated between 0 and 1.
For example, if ZEROWEIGHT=2 and FULLWEIGHT=1,
a value 1.3 standard deviations from the mean
would be assigned a graduated weight.
The default is ZEROWEIGHT=2.5.
The ZEROWEIGHT option can be used
in conjunction with the FULLWEIGHT= option
to adjust outliers from a monthly or
quarterly series.
See Example 21.3 later in
this chapter for an illustration of this use.
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.