In Jim Cramer's opinion, the only way to get real growth in retail is to grow as a country. There are two ways to grow; either with new families, or immigration. That is it.

"Nothing else can really help us long term, including by the way, the oft-mentioned Federal Reserve. That's right, over a long enough time horizon, population growth leads to economic growth," the "Mad Money" host said.

Unfortunately population growth, both from new households and from an immigration standpoint, has been a problem ever since the great recession. And this has been behind a lot of the issues in the U.S.; it's just not talked about.

The one person openly talking about this issue was Carol Tome, CFO of Home Depot when she placed it as the core context of consumer spending for her company.

Once the great recession started, household formation numbers dropped dramatically to about 500,000 new homes a year from approximately 1.3 million, Cramer said.

However, now things seem to be back on track. Home Depot just confirmed a household formation figure of more than 1 million homes. As a result, the Home Depot CFO said she expects to see a dramatic increase in growth for the company.

Cramer doesn't know if this is a real trend, though. Warren Buffett famously discussed how human hormones, and the need to have children, would get housing back on track. But that was three years ago and didn't happen.

"If it happened now, though, it could really make a difference to sales for the whole retail cohort," Cramer said.

It should also be pointed out that household formation isn't the only thing that matters for retail sales. Employment, growing salaries and credit matter as well. Tome also indicated that she is seeing these numbers starting to thaw as well.

The reason why household formation numbers are so important is because that will spark confidence in the value of housing. If more people are confident in their houses moving up in value, then they will buy goods for their home as an investment.

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And that is exactly why Home Depot is seeing better than expected numbers, as people are starting to spend more on the big ticket items for their home.

This trend is so important to Cramer, yet no one seems to realize what Home Depot's growth really means. This is also why hard goods are being favored over soft goods.

"Watch this household number. This is the rising tide…Ultimately this trend will pull up all household spending, and then the real, long-waited recovery will finally begin."

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