Green card and passport stamp give different dates

[Ingela Thuné]

Hi there,
I'm confused about something. I'm married to an American and got my green card valied for two years. However, I noticed that my passport stamp from immigration (when I entered the States with my immigration visa), says one year. Should this stamp not say two years as the greencard does? What if I need to leave the States for a holiday for example after the first year is up? I wondered if it was a mistake as the guy at the airport immigration was very distracted. Thanks in advance for any help.