NEW YORK ( TheStreet) -- Pending home sales plunged 30% in May, as the tax credit for home buyers came to an end -- evincing, perhaps, just how weak the sector still is without government support. According to the National Association of Realtors, the Pending Home Sales Index dropped to 77.6 during the month from 110.9 in April. This is also about 16% lower than the 92.3 reading in May 2009. Economists were predicting a much smaller 12.5% drop. As a result, shares of homebuilders are in the red Thursday morning. KB Homes ( KBH) is falling 1.4% to $10.85, MDC ( MDC) is dropping 2% to $26.42, PulteGroup ( PHM) is off 1% to $8.18 and DR Horton ( DHI) is declining 0.8% to $9.75. All four regions saw decreases in May, led by a 33% plunge in the South. Sales also fell 32% in both the Midwest and Northeast and 21% in the West. The tax credit, which was worth up to $8,000, helped fuel a rebound in demand last year. Due to this success, the credit was extended and required buyers to sign contracts by the end of April and close by June 30. The House of Representatives voted this week to push back the closing deadline to Sept. 30. -- Reported by Jeanine Poggi in New York. Follow TheStreet.com on Twitter and become a fan on Facebook.