def METHOD_NAME(self) -> bool:
    if not self.index._is_strictly_monotonic_increasing:
        print(
            "WARNING: Date index not monotonically increasing in following indices:"
        )
        not_monotonic = self.index[1:][self.index[1:] <= self.index[:-1]]
        print(not_monotonic)
        return False
    else:
        return True