public String getTagValue(final String tagName) {
        return timeAgnosticStatisticEvent.getTagValue(tagName);
    }
Convenience method for extracting the value of a tag in this statistic event

@param tagName The name of the tag to extract
@return The value of the named tag
stroom-statistics/stroom-statistics-impl-sql/src/main/java/stroom/statistics/impl/sql/StatisticEvent.java