NEW YORK (CNN/Money) - Some economists are starting to talk about deflation. If the economy enters a deflationary period, what is the best way to protect one's assets?

Hey, economists talk about a lot of things. But that doesn't mean we should take them seriously. After all, these are economists, the guys who didn't figure out until earlier this month that the economy has been in recession since March.

What's probably generated this deflation talk is that we've seen some flat-to-down numbers lately in the government's main gauge for inflation, the consumer price index, which is a monthly measure of the change in the price of a basket of goods and services such as housing, energy, transportation and food. In July and October, for example, the consumer price index -- or the CPI as the economists would say -- declined 0.3 percent from the previous month, and the index was flat for the month of November. Similarly, the producer price index, or PPI, which monitors price changes in the goods and services sold among businesses, has also shown some declines this year.

But you've got to be careful about drawing any conclusions from just a few months of data. First of all, we're in a recession now, which is usually a time when inflation is at its most mild. I'd expect that to change once the economy begins to recover.

Second, there's a lot of "noise" in these inflation numbers -- that is, because they're statistical estimates based on samples of goods, these figures can jump around quite a bit on a month-to-month basis. Often, they're revised several months later, at which point the final number may end up being higher or lower than the one originally reported. In addition, big changes in certain goods or services can often sway the entire index. For example, the prices of food and energy, both of which can be heavily influenced by the weather, will sometimes make wild swings, giving a false impression of what's going on with inflation overall.

The CPI was flat in November, for example, but that was largely because falling oil prices sent the petroleum-based energy index down 9.4 percent. To avoid being misled by huge swings in volatile sectors, many CPI watchers follow what they refer to as the "core" CPI -- that is, the CPI minus food and energy. In November, the core rate of inflation actually rose 0.4 percent from the previous month.

All in all, I wouldn't hold my breath waiting for a sustained period of deflation -- that is, price declines -- in the U.S. In fact, the only time we experienced deflation for any length of time was during the 1930's, a decade during which prices declined almost 20 percent. And it took the Great Depression to trigger that spate of declining prices. Unless you think we're going to experience something along those lines again, arranging your portfolio to take advantage of declining prices would seem, well, counterproductive to say the least.

But, if you want to know what you ought to buy in the unlikely event deflation does reappear, then I'd say your best bet is probably bonds, and long-term bonds at that.

The reason is that during periods of deflation future dollars are more valuable than present dollars because they can buy more goods -- in short, the opposite of what happens during periods of inflation. So by buying bonds, the dollars you get in interest payments and repayment of principal are more valuable than the dollars you invested.

Stocks, on the other hand, have a harder time during periods of deflation because companies have a hard time getting enough revenue to recoup their costs when the prices they get for their products are declining. And, indeed, during the 1930's, large-company stocks lost an annualized 0.5 percent per year, while long-term corporate bonds gained an annualized 7 percent. But, as I said, I wouldn't hold my breath waiting for a reprise of the 1930s.