Is the Rate of Single-Family Home Construction Going Down?

Berkshire owns many companies that benefit from single-family home construction. Could something more secular be going on where household formation rates relative to the population could continue to be lower than historical rates? Do you think still that the subdued rate of household formation is mostly a cyclical phenomenon or at the rate will eventually revert to the historical mean boosting single-family earnings for this group of companies? I don't know the answer obviously but I think I think the latter is more likely and I may be wrong what when's the last set of figures you've looked at, Jonathan asked Berkshire CEO Charlie Warren.