Passage: As of the census of 2000, there were 735 people, 284 households, and 241 families residing in the village. The population density was 92.1 people per square mile (35.6/km2). Of the 735 people, 728 of them are white. There were 317 housing units at an average density of 39.7 per square mile (15.3/km2). The racial makeup of the village was 99.05% White, 0.14% African American, 0.68% Asian, and 0.14% from two or more races. Hispanic or Latino of any race were 0.54% of the population. 17.4% were of English, 17.1% German, 11.0% Irish, 9.0% Italian, 5.7% American and 5.6% Russian ancestry according to Census 2000.

Question: How many housing unit are in the village?
317