NEW YORK (CNN/Money) - Inflation ... is it or isn't it? On a steady march higher, that is.

When Fed chief Alan Greenspan testified last week, he didn't sound the least bit worried. He said that overall inflation had subsided and that the core rate (takes out food and energy) "has remained low." So it's hard to believe he would be freaked out by Friday's big jump in the producer price index, but that big jump in PPI is why markets are even more focused on today's consumer price index.

A couple of things to keep in mind.

The PPI measures wholesale prices, basically business-to-business prices; the CPI measures retail prices, what you and I buy in the store. The CPI is also much more heavily weighted toward the prices of services like doctor's visits and tuition costs. In fact, less than the half of the CPI is made up of goods prices. These aspects are what makes it more important than the PPI, by far.

Today's CPI number was what folks expected: a rise of 0.1 percent, the core up 0.2 percent. It's a gain, yes. But that much more of a gain? We may need some more data.

Mr. G's favorite inflation indicator is the "core PCE deflator" (that thing needs a new name!), part of the Personal Income and Consumption report due out later this month.

Oil prices above $50 bucks a barrel today are one more reason why some folks are more worried about inflation, especially those who think the economy is strong enough for producers to pass those prices on to consumers without hurting spending in households where incomes are low and higher energy costs take a relatively bigger bite.

The moral of today's inflation story may lie not so much in the CPI report and the market's reaction to it, but in the release of the minutes of the Fed's last meeting in February. There we may get a better sense of just how worried or not worried Greenspan's colleagues are about inflation and if there is a move afoot to take stronger action in the weeks ahead to keep prices in check.

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-- Kathleen Hays is economics correspondent for CNN and contributes to Lou Dobbs Tonight.