Time Format Alternate Half Year

At ESCB level SDMX data exchanges, there is an agreement to use 'H' as the frequency value for semiannual observations. This is specified via 'YYYY-H1' or 'YYYY-H2'.

The Registry supports this by setting a system property so the Registry is in 'alternate half year' mode. Under this mode:

• Frequency value 'H' means half-year (semiannual or semester)
• The hourly frequency is not supported
• 'YYYY-S1' and 'YYYY-H1' are valid TIME_PERIOD formats for half-yearly observations, however conversion will output in ‘YYYY-H1’ format

Alternate half year mode is controlled at system level on Registry start-up by setting the Java System variable "TF_ALTERNATE_HALF_YEAR" to "true".

Setting System Property

If using Apache Tomcat, it is recommended to set the value via JAVA_OPTS and using the setenv.bat or setenv.sh file:

SET JAVA_OPTS=-DTF_ALTERNATE_HALF_YEAR=true
(For Windows systems)

export JAVA_OPTS=-DTF_ALTERNATE_HALF_YEAR=true
(For Unix systems)

Different procedures may be required for other web application servers like JBoss.

Is Alternate Half-Year Format set?

On startup the Fusion Registry system log will report the following message:

2021-12-31 23:59:59.123 INFO main io.sdmx.core.fmr.application.FusionRegistryApplicationInitialiser - Using 'Alternate Half-Year' Setting

Active system properties can also be queried using the REST API which is detailed here.