constructor(key: MetricKey<DatasetSolvedRateMetric> = KEY, itemsFinished: Int = 0, itemsSolved: Int = 0, itemsNotSolved: Int = 0, itemsFailed: Int = 0, solvedRatio: Ratio = Ratio.ZERO, notSolvedRatio: Ratio = Ratio.ZERO, failedRatio: Ratio = Ratio.ZERO)