April 1 is a reference date, not a deadline to respond. When you respond online, by phone, or by mail, count everyone living in your home as of April 1. Your response matters. Health clinics. Fire departments. Schools. Even roads and highways. The census can shape many different aspects of your community. Census results help determine how billions of dollars in federal funding flow into states and communities each year. The results determine how many seats in Congress each state gets. It’s mandated by the U.S. Constitution in Article 1, Section 2: The U.S. has counted its population every 10 years since 1790.