key: name of the counter. It should comply with IEEE Std 1003.1-2001 conventions, unless brackets {} are adopted to refer it.
values: list of the string values (labels) of the counter. Multiple-value field: list of dimensions separated by “|” can be provided. Current value can be accessed with @key or @{key}.
counter: subset string of the values to be assigned to the counter. Current value can be accessed with &key or &{key}.
parallel: set to “yes” in case of parallel processing; sequential processing is the default. At least one of arguments “values” or “counter” has to be set. By default, “counter” will be set to “1” in case “values” is not provided.
