The Mortgage Bankers Association reports today that rates on 30-year mortgages fell from 4.89 percent last week to a current figure of 4.63 percent. Unsurprisingly, the refinance rate jumped as a result, increasing 72.9 percent during that span as opportunistic homeowners scrambled to reduce their existing interest rates.

In fact, more than 75 percent of those applicants were current homeowners and the remainder came from new homebuyers.

An Associated Press report tells us how it all came to be:

“Interest rates have plunged since the Federal Reserve said in November it would buy up to $500 billion in mortgage-backed securities in an effort to bolster the long-suffering housing market. Last week, the Federal Reserve went further, announcing a $1.2 trillion effort to lower rates on mortgages and other consumer debt in a bid to revive the economy. The effort includes buying up to $300 billion in long-term government bonds and $750 billion in mortgage-backed securities guaranteed by Fannie Made and Freddie Mac.”

Up until recently most homeowners were unable to take advantage of the great rates because of the collective nosedive that the housing market took in the past few years. They became upside-down on their mortgages, meaning that they owed their lenders more than their homes were worth .

Refinancing under those conditions was next to impossible.

The good news is things are a little different now thanks to the “Making Home Affordable” program, which was introduced on March 4 to “stimulate” the housing market and reduce interest rates/loan amounts for homeowners struggling to meet their monthly mortgage obligations.

For more on the particulars of that program click here.