NEW YORK (CNNMoney.com) - Mortgage rates stayed relatively unchanged this week after contradictory economic data left the bond market unsure over the direction the economy.

The average rate on 30-year fixed-rate mortgages was 6.63, for the week ending June 15, from the prior week's 6.62 percent -- that had been the highest level since June 2002, according to Freddie Mac's mortgage survey. In the year-ago period, the 30-year mortgage rate averaged 5.63 percent.

Mixed economic signals from the past week have sent conflicting messages to the bond market. The consumer price index came in higher than expected on Wednesday, raising expectations the Fed will raise short-term rates to cool off economic growth. However, the Fed's "beige book" report, released the same day, indicated the economy might already be slowing.

Frank Nothaft, Freddie Mac vice president and chief economist, said volatility in financial markets leads to mortgage rate fluctuations. "Still, there has been no drastic movement in mortgage rates and we see nothing on the horizon that would bring about any extreme rise or fall in rates going forward," Nothaft said.

The average rate on 15-year fixed-rate mortgages rose to 6.25 percent from 6.23 percent last week. A year ago, that loan averaged 5.22 percent.

Five-year adjustable-rate mortgages averaged 6.23 percent, 0.03 higher than last week. The five-year ARM averaged 5.10 percent last year.

The average one-year adjustable-rate mortgage rose to 5.66 percent from 5.63 percent. At this time last year, the one-year loan averaged 4.25 percent.

Although this week's numbers were not significantly higher, rates are up for the year. For homeowners using adjustable rate mortgages, a rise in interest rates can mean ballooning payments.

The Mortgage Bankers Association estimates that some $330 billion worth of ARMs will adjust in 2006 and $1 trillion worth will reset by the end of 2007. With a $200,000 loan adjusting upward from 4 percent to 6 percent, the monthly bill would increase to about $1,200, from $955.