Zelman: Census home sales data inaccurate

The Census Department’s data on new construction sales is wildy inaccurate, housing analyst Ivy Zelman told CNBC.com.

According to Zelman’s data, December estimates showed a 12 percent decline in seasonally adjusted new home sales, which she said was consistent with data from builders. But the Census reported an 18 percent increase. Moreover, Zelman’s survey suggested an 11 percent increase on new home orders compared to a year ago, while the Census reported a 13 percent decline.

"While it would appear that the Census’ numbers are troubling for new home sales, and you are right that new home inventory is depressed, we believe the new home sales pace is materially above what the Census has reported in recent months, suggesting there is not as much ‘doom and gloom’ on the new home side as what is being widely reported," Zelman said.

Much of the variation could be due to small sample size. As a result, the Census data has a very large margin of error, hitting +/- 82.5 percent in January.