public long GetPopulationWithAnyFeature(CohortFeatures features) => m_cohorts.Where(x => (x.Features & features) != CohortFeatures.None).Sum(x => x.Population);
public long GetPopulationWithAllFeatures(CohortFeatures features) => m_cohorts.Where(x => (x.Features & features) == features).Sum(x => x.Population);
public CohortTemplate(CohortFeatures features, TimeOffset startAge, TimeOffset pastEndAge) { Features = features; StartAge = startAge; PastEndAge = pastEndAge; }